Combining Philosophers

All the ideas for Alfred Tarski, M Loux / D Zimmerman and PG

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291 ideas

1. Philosophy / B. History of Ideas / 3. Greek-English Lexicon
Agathon: good [PG]
     Full Idea: Agathon: good, the highest good
     From: PG (Db (lexicon) [c.1001 BCE], 01)
Aisthesis: perception, sensation, consciousness [PG]
     Full Idea: Aisthesis: perception, sensation, consciousness
     From: PG (Db (lexicon) [c.1001 BCE], 02)
Aitia / aition: cause, explanation [PG]
     Full Idea: Aitia / aition: cause, explanation
     From: PG (Db (lexicon) [c.1001 BCE], 03)
     A reaction: The consensus is that 'explanation' is the better translation, and hence that the famous Four Causes (in 'Physics') must really be understood as the Four Modes of Explanation. They then make far more sense.
Akrasia: lack of control, weakness of will [PG]
     Full Idea: Akrasia: lack of control, weakness of will
     From: PG (Db (lexicon) [c.1001 BCE], 04)
     A reaction: The whole Greek debate (and modern debate, I would say) makes much more sense if we stick to 'lack of control' as the translation, and forget about weakness of will - and certainly give up 'incontinence' as a translation.
Aletheia: truth [PG]
     Full Idea: Aletheia: truth
     From: PG (Db (lexicon) [c.1001 BCE], 05)
Anamnesis: recollection, remembrance [PG]
     Full Idea: Anamnesis: recollection, remembrance
     From: PG (Db (lexicon) [c.1001 BCE], 06)
     A reaction: This is used for Plato's doctrine that we recollect past lives.
Ananke: necessity [PG]
     Full Idea: Ananke: necessity
     From: PG (Db (lexicon) [c.1001 BCE], 07)
Antikeimenon: object [PG]
     Full Idea: Antikeimenon: object
     From: PG (Db (lexicon) [c.1001 BCE], 08)
Apatheia: unemotional [PG]
     Full Idea: Apatheia: lack of involvement, unemotional
     From: PG (Db (lexicon) [c.1001 BCE], 09)
Apeiron: the unlimited, indefinite [PG]
     Full Idea: Apeiron: the unlimited, indefinite
     From: PG (Db (lexicon) [c.1001 BCE], 10)
     A reaction: Key term in the philosophy of Anaximander, the one unknowable underlying element.
Aphairesis: taking away, abstraction [PG]
     Full Idea: Aphairesis: taking away, abstraction
     From: PG (Db (lexicon) [c.1001 BCE], 11)
Apodeixis: demonstration [PG]
     Full Idea: Apodeixis: demonstration, proof
     From: PG (Db (lexicon) [c.1001 BCE], 12)
Aporia: puzzle, question, anomaly [PG]
     Full Idea: Aporia: puzzle, question, anomaly
     From: PG (Db (lexicon) [c.1001 BCE], 13)
Arche: first principle, the basic [PG]
     Full Idea: Arché: first principle, the basic
     From: PG (Db (lexicon) [c.1001 BCE], 14)
     A reaction: Interchangeable with 'aitia' by Aristotle. The first principle and the cause are almost identical.
Arete: virtue, excellence [PG]
     Full Idea: Areté: virtue, excellence
     From: PG (Db (lexicon) [c.1001 BCE], 15)
     A reaction: The word hovers between moral excellence and being good at what you do. Annas defends the older translation as 'virtue', rather than the modern 'excellence'.
Chronismos: separation [PG]
     Full Idea: Chronismos: separation
     From: PG (Db (lexicon) [c.1001 BCE], 16)
Diairesis: division [PG]
     Full Idea: Diairesis: division, distinction
     From: PG (Db (lexicon) [c.1001 BCE], 17)
Dialectic: dialectic, discussion [PG]
     Full Idea: Dialectic: dialectic, discussion
     From: PG (Db (lexicon) [c.1001 BCE], 18)
Dianoia: intellection [cf. Noesis] [PG]
     Full Idea: Dianoia: intellection, understanding [cf. Noesis]
     From: PG (Db (lexicon) [c.1001 BCE], 21)
Diaphora: difference [PG]
     Full Idea: Diaphora: difference
     From: PG (Db (lexicon) [c.1001 BCE], 22)
Dikaiosune: moral goodness, justice [PG]
     Full Idea: Dikaiosune: moral goodness, justice
     From: PG (Db (lexicon) [c.1001 BCE], 23)
     A reaction: Usually translated as 'justice' in 'Republic', but it is a general term of moral approbation, not like the modern political and legal notion of 'justice'. 'Justice' actually seems to be bad translation.
Doxa: opinion, belief [PG]
     Full Idea: Doxa: opinion, belief, judgement
     From: PG (Db (lexicon) [c.1001 BCE], 24)
Dunamis: faculty, potentiality, capacity [PG]
     Full Idea: Dunamis: faculty, potentiality, capacity
     From: PG (Db (lexicon) [c.1001 BCE], 25)
Eidos: form, idea [PG]
     Full Idea: Eidos: form, idea
     From: PG (Db (lexicon) [c.1001 BCE], 26)
     A reaction: In Plato it is the word best translated as 'Form' (Theory of...); in Aritotle's 'Categories' it designates the species, and in 'Metaphysics' it ends up naming the structural form of the species (and hence the essence) [Wedin p.120]
Elenchos: elenchus, interrogation [PG]
     Full Idea: Elenchos: elenchus, interrogation
     From: PG (Db (lexicon) [c.1001 BCE], 27)
Empeiron: experience [PG]
     Full Idea: Empeiron: experience
     From: PG (Db (lexicon) [c.1001 BCE], 28)
Energeia: employment, actuality, power? [PG]
     Full Idea: Energeia: employment, actuality, power?
     From: PG (Db (lexicon) [c.1001 BCE], 31)
Enkrateia: control [PG]
     Full Idea: Enkrateia: control
     From: PG (Db (lexicon) [c.1001 BCE], 32)
     A reaction: See 'akrasia', of which this is the opposite. The enkratic person is controlled.
Entelecheia: entelechy, having an end [PG]
     Full Idea: Entelecheia: entelechy, having an end
     From: PG (Db (lexicon) [c.1001 BCE], 33)
Epagoge: induction, explanation [PG]
     Full Idea: Epagoge: induction, explanation, leading on
     From: PG (Db (lexicon) [c.1001 BCE], 34)
Episteme: knowledge, understanding [PG]
     Full Idea: Episteme: knowledge, understanding
     From: PG (Db (lexicon) [c.1001 BCE], 35)
     A reaction: Note that 'episteme' can form a plural in Greek, but we can't say 'knowledges', so we have to say 'branches of knowledge', or 'sciences'.
Epithumia: appetite [PG]
     Full Idea: Epithumia: appetite
     From: PG (Db (lexicon) [c.1001 BCE], 36)
Ergon: function [PG]
     Full Idea: Ergon: function, work
     From: PG (Db (lexicon) [c.1001 BCE], 37)
Eristic: polemic, disputation [PG]
     Full Idea: Eristic: polemic, disputation
     From: PG (Db (lexicon) [c.1001 BCE], 38)
     A reaction: This is confrontational argument, rather than the subtle co-operative dialogue of dialectic. British law courts and the House of Commons are founded on eristic, rather than on dialectic. Could there be a dialectical elected assembly?
Eros: love [PG]
     Full Idea: Eros: love, desire
     From: PG (Db (lexicon) [c.1001 BCE], 41)
Eudaimonia: flourishing, happiness, fulfilment [PG]
     Full Idea: Eudaimonia: flourishing, happiness, fulfilment
     From: PG (Db (lexicon) [c.1001 BCE], 42)
     A reaction: Some people defend 'happiness' as the translation, but that seems to me wildly misleading, since eudaimonia is something like life going well, and certainly isn't a psychological state - and definitely not pleasure.
Genos: type, genus [PG]
     Full Idea: Genos: type, genus, kind
     From: PG (Db (lexicon) [c.1001 BCE], 43)
Hexis: state, habit [PG]
     Full Idea: Hexis: state, habit
     From: PG (Db (lexicon) [c.1001 BCE], 44)
Horismos: definition [PG]
     Full Idea: Horismos: definition
     From: PG (Db (lexicon) [c.1001 BCE], 45)
Hule: matter [PG]
     Full Idea: Hule: matter
     From: PG (Db (lexicon) [c.1001 BCE], 46)
     A reaction: The first half of the 'hylomorphism' of Aristotle. See 'morphe'!
Hupokeimenon: subject, underlying thing [cf. Tode ti] [PG]
     Full Idea: Hupokeimenon: subject, underlying thing, substratum [cf. Tode ti]
     From: PG (Db (lexicon) [c.1001 BCE], 47)
     A reaction: Literally 'that which lies under'. Latin version is 'substratum'. In Aristotle it is the problem, of explaining what lies under. It is not the theory that there is some entity called a 'substratum'.
Kalos / kalon: beauty, fineness, nobility [PG]
     Full Idea: Kalos / kalon: beauty, fineness, nobility
     From: PG (Db (lexicon) [c.1001 BCE], 48)
     A reaction: A revealing Greek word, which is not only our rather pure notion of 'beauty', but also seems to mean something like wow!, and (very suggestive, this) applies as much to actions as to objects.
Kath' hauto: in virtue of itself, essentially [PG]
     Full Idea: Kath' hauto: in virtue of itself, essentially
     From: PG (Db (lexicon) [c.1001 BCE], 51)
Kinesis: movement, process [PG]
     Full Idea: Kinesis: movement, process, change
     From: PG (Db (lexicon) [c.1001 BCE], 52)
Kosmos: order, universe [PG]
     Full Idea: Kosmos: order, universe
     From: PG (Db (lexicon) [c.1001 BCE], 53)
Logos: reason, account, word [PG]
     Full Idea: Logos: reason, account, word
     From: PG (Db (lexicon) [c.1001 BCE], 54)
Meson: the mean [PG]
     Full Idea: Meson: the mean
     From: PG (Db (lexicon) [c.1001 BCE], 55)
     A reaction: This is not the 'average', and hence not some theoretical mid-point. I would call it the 'appropriate compromise', remembering that an extreme may be appropriate in certain circumstances.
Metechein: partaking, sharing [PG]
     Full Idea: Metechein: partaking, sharing
     From: PG (Db (lexicon) [c.1001 BCE], 56)
     A reaction: The key word in Plato for the difficult question of the relationships between the Forms and the particulars. The latter 'partake' of the former. Hm. Compare modern 'instantiation', which strikes me as being equally problematic.
Mimesis: imitation, fine art [PG]
     Full Idea: Mimesis: imitation, fine art
     From: PG (Db (lexicon) [c.1001 BCE], 57)
Morphe: form [PG]
     Full Idea: Morphe: form
     From: PG (Db (lexicon) [c.1001 BCE], 58)
Noesis: intellection, rational thought [cf. Dianoia] [PG]
     Full Idea: Noesis: intellection, rational thought [cf. Dianoia]
     From: PG (Db (lexicon) [c.1001 BCE], 59)
Nomos: convention, law, custom [PG]
     Full Idea: Nomos: convention, law, custom
     From: PG (Db (lexicon) [c.1001 BCE], 61)
Nous: intuition, intellect, understanding [PG]
     Full Idea: Nous: intuition, intellect
     From: PG (Db (lexicon) [c.1001 BCE], 62)
     A reaction: There is a condensed discussion of 'nous' in Aristotle's Posterior Analytics B.19
Orexis: desire [PG]
     Full Idea: Orexis: desire
     From: PG (Db (lexicon) [c.1001 BCE], 63)
Ousia: substance, (primary) being, [see 'Prote ousia'] [PG]
     Full Idea: Ousia: substance, (primary) being [see 'Prote ousia']
     From: PG (Db (lexicon) [c.1001 BCE], 64)
     A reaction: It is based on the verb 'to be'. Latin therefore translated it as 'essentia' (esse: to be), and we have ended up translating it as 'essence', but this is wrong! 'Being' is the best translation, and 'substance' is OK. It is the problem, not the answer.
Pathos: emotion, affection, property [PG]
     Full Idea: Pathos: emotion, affection, property
     From: PG (Db (lexicon) [c.1001 BCE], 65)
Phantasia: imagination [PG]
     Full Idea: Phantasia: imagination
     From: PG (Db (lexicon) [c.1001 BCE], 66)
Philia: friendship [PG]
     Full Idea: Philia: friendship
     From: PG (Db (lexicon) [c.1001 BCE], 67)
Philosophia: philosophy, love of wisdom [PG]
     Full Idea: Philosophia: philosophy, love of wisdom
     From: PG (Db (lexicon) [c.1001 BCE], 68)
     A reaction: The point of the word is its claim only to love wisdom, and not actually to be wise.
Phronesis: prudence, practical reason, common sense [PG]
     Full Idea: Phronesis: prudence, practical reason, common sense
     From: PG (Db (lexicon) [c.1001 BCE], 71)
     A reaction: None of the experts use my own translation, which is 'common sense', but that seems to me to perfectly fit all of Aristotle's discussions of the word in 'Ethics'. 'Prudence' seems a daft translation in modern English.
Physis: nature [PG]
     Full Idea: Physis: nature
     From: PG (Db (lexicon) [c.1001 BCE], 72)
Praxis: action, activity [PG]
     Full Idea: Praxis: action, activity
     From: PG (Db (lexicon) [c.1001 BCE], 73)
Prote ousia: primary being [PG]
     Full Idea: Prote ousia: primary being
     From: PG (Db (lexicon) [c.1001 BCE], 74)
     A reaction: The main topic of investigation in Aristotle's 'Metaphysics'. 'Ousia' is the central problem of the text, NOT the answer to the problem.
Psuche: mind, soul, life [PG]
     Full Idea: Psuche: mind, soul, life
     From: PG (Db (lexicon) [c.1001 BCE], 75)
     A reaction: The interesting thing about this is that we have tended to translate it as 'soul', but Aristotle says plants have it, and not merely conscious beings. It is something like the 'form' of a living thing, but then 'form' is a misleading translation too.
Sophia: wisdom [PG]
     Full Idea: Sophia: wisdom
     From: PG (Db (lexicon) [c.1001 BCE], 76)
Sophrosune: moderation, self-control [PG]
     Full Idea: Sophrosune: moderation, self-control
     From: PG (Db (lexicon) [c.1001 BCE], 77)
Stoicheia: elements [PG]
     Full Idea: Stoicheia: elements
     From: PG (Db (lexicon) [c.1001 BCE], 78)
Sullogismos: deduction, syllogism [PG]
     Full Idea: Sullogismos: deduction, syllogism
     From: PG (Db (lexicon) [c.1001 BCE], 81)
Techne: skill, practical knowledge [PG]
     Full Idea: Techne: skill, practical knowledge
     From: PG (Db (lexicon) [c.1001 BCE], 82)
Telos: purpose, end [PG]
     Full Idea: Telos: purpose, end
     From: PG (Db (lexicon) [c.1001 BCE], 83)
Theoria: contemplation [PG]
     Full Idea: Theoria: contemplation
     From: PG (Db (lexicon) [c.1001 BCE], 84)
Theos: god [PG]
     Full Idea: Theos: god
     From: PG (Db (lexicon) [c.1001 BCE], 85)
Ti esti: what-something-is, essence [PG]
     Full Idea: Ti esti: the what-something-is, essence, whatness
     From: PG (Db (lexicon) [c.1001 BCE], 86)
Timoria: vengeance, punishment [PG]
     Full Idea: Timoria: vengeance, punishment
     From: PG (Db (lexicon) [c.1001 BCE], 87)
To ti en einai: essence, what-it-is-to-be [PG]
     Full Idea: To ti en einai: essence, what-it-is-to-be
     From: PG (Db (lexicon) [c.1001 BCE], 88)
     A reaction: This is Aristotle's main term for what we would now call the 'essence'. It is still not a theory of essence, merely an identification of the target. 'Form' is the nearest we get to his actual theory.
To ti estin: essence [PG]
     Full Idea: To ti estin: essence
     From: PG (Db (lexicon) [c.1001 BCE], 91)
Tode ti: this-such, subject of predication [cf. hupokeimenon] [PG]
     Full Idea: Tode ti: this-something, subject of predication, thisness [cf. hupokeimenon]
     From: PG (Db (lexicon) [c.1001 BCE], 92)
1. Philosophy / C. History of Philosophy / 2. Ancient Philosophy / a. Ancient chronology
323 (roughly): Euclid wrote 'Elements', summarising all of geometry [PG]
     Full Idea: Euclid: In around 323 BCE Euclid wrote his 'Elements', summarising all of known geometry.
     From: PG (Db (chronology) [2030])
1000 (roughly): Upanishads written (in Sanskrit); religious and philosophical texts [PG]
     Full Idea: In around 1000 BCE the Upanishads were written, the most philosophical of ancient Hindu texts
     From: PG (Db (chronology) [2030], 0001)
750 (roughly): the Book of Genesis written by Hebrew writers [PG]
     Full Idea: In around 750 BCE the Book of Genesis was written by an anonymous jewish writer
     From: PG (Db (chronology) [2030], 0250)
586: eclipse of the sun on the coast of modern Turkey was predicted by Thales of Miletus [PG]
     Full Idea: In 585 BCE there was an eclipse of the sun, which Thales of Miletus is said to have predicted
     From: PG (Db (chronology) [2030], 0415)
570: Anaximander flourished in Miletus [PG]
     Full Idea: Anaximander: In around 570 BCE the philosopher and astronomer Anaximander flourished in Miletus
     From: PG (Db (chronology) [2030], 0430)
563: the Buddha born in northern India [PG]
     Full Idea: In around 563 BCE Siddhartha Gautama, the Buddha, was born in northern India
     From: PG (Db (chronology) [2030], 0437)
540: Lao Tzu wrote 'Tao Te Ching', the basis of Taoism [PG]
     Full Idea: In around 540 BCE Lao Tzu wrote the 'Tao Te Ching', the basis of Taoism
     From: PG (Db (chronology) [2030], 0460)
529: Pythagoras created his secretive community at Croton in Sicily [PG]
     Full Idea: In around 529 BCE Pythagoras set up a community in Croton, with strict and secret rules and teachings
     From: PG (Db (chronology) [2030], 0471)
500: Heraclitus flourishes at Ephesus, in modern Turkey [PG]
     Full Idea: In around 500 BCE Heraclitus flourished in the city of Ephesus in Ionia
     From: PG (Db (chronology) [2030], 0500)
496: Confucius travels widely, persuading rulers to be more moral [PG]
     Full Idea: In 496 BCE Confucius began a period of wandering, to persuade rulers to be more moral
     From: PG (Db (chronology) [2030], 0504)
472: Empedocles persuades his city (Acragas in Sicily) to become a democracy [PG]
     Full Idea: In 472 BCE Empedocles helped his city of Acragas change to democracy
     From: PG (Db (chronology) [2030], 0528)
450 (roughly): Parmenides and Zeno visit Athens from Italy [PG]
     Full Idea: In around 450 BCE Parmenides and Zeno visited the festival in Athens
     From: PG (Db (chronology) [2030], 0550)
445: Protagoras helps write laws for the new colony of Thurii [PG]
     Full Idea: In 443 BCE Protagoras helped write the laws for the new colony of Thurii
     From: PG (Db (chronology) [2030], 0557)
436 (roughly): Anaxagoras is tried for impiety, and expelled from Athens [PG]
     Full Idea: In about 436 BCE Anaxagoras was tried on a charge of impiety and expelled from Athens
     From: PG (Db (chronology) [2030], 0564)
427: Gorgias visited Athens as ambassador for Leontini [PG]
     Full Idea: In 427 BCE Gorgias of Leontini visited Athens as an ambassador for his city
     From: PG (Db (chronology) [2030], 0573)
399: Socrates executed (with Plato absent through ill health) [PG]
     Full Idea: In 399 BCE Plato was unwell, and was not present at the death of Socrates
     From: PG (Db (chronology) [2030], 0601)
387 (roughly): Plato returned to Athens, and founded the Academy [PG]
     Full Idea: In about 387 BCE Plato returned to Athens and founded his new school at the Academy
     From: PG (Db (chronology) [2030], 0613)
387 (roughly): Aristippus the Elder founder a hedonist school at Cyrene [PG]
     Full Idea: In around 387 BCE a new school was founded at Cyrene by Aristippus the elder
     From: PG (Db (chronology) [2030], 0613)
367: the teenaged Aristotle came to study at the Academy [PG]
     Full Idea: In 367 BCE the seventeen-year-old Aristotle came south to study at the Academy
     From: PG (Db (chronology) [2030], 0633)
360 (roughly): Diogenes of Sinope lives in a barrel in central Athens [PG]
     Full Idea: In around 360 BCE Diogenes of Sinope was living in a barrel in the Agora in Athens
     From: PG (Db (chronology) [2030], 0640)
347: death of Plato [PG]
     Full Idea: In 347 BCE Plato died
     From: PG (Db (chronology) [2030], 0653)
343: Aristotle becomes tutor to 13 year old Alexander (the Great) [PG]
     Full Idea: In 343 BCE at Stagira Aristotle became personal tutor to the thirteen-year-old Alexander (the Great)
     From: PG (Db (chronology) [2030], 0657)
335: Arisotle founded his school at the Lyceum in Athens [PG]
     Full Idea: In 335 BCE Aristotle founded the Lyceum in Athens
     From: PG (Db (chronology) [2030], 0665)
330 (roughly): Chuang Tzu wrote his Taoist book [PG]
     Full Idea: In around 330 BCE Chuang Tzu wrote a key work in the Taoist tradition
     From: PG (Db (chronology) [2030], 0670)
322: Aristotle retired to Chalcis, and died there [PG]
     Full Idea: In 322 BCE Aristotle retired to Chalcis in Euboea, where he died
     From: PG (Db (chronology) [2030], 0678)
307 (roughly): Epicurus founded his school at the Garden in Athens [PG]
     Full Idea: In about 307 BCE Epicurus founded his school at the Garden in Athens
     From: PG (Db (chronology) [2030], 0693)
301 (roughly): Zeno of Citium founded Stoicism at the Stoa Poikile in Athens [PG]
     Full Idea: In about 301 BCE the Stoic school was founded by Zeno of Citium in the Stoa Poikile in Athens
     From: PG (Db (chronology) [2030], 0699)
261: Cleanthes replaced Zeno as head of the Stoa [PG]
     Full Idea: In 261 BCE Cleanthes took over from Zeno as head of the Stoa.
     From: PG (Db (chronology) [2030], 0739)
229 (roughly): Chrysippus replaced Cleanthes has head of the Stoa [PG]
     Full Idea: In about 229 BCE Chrysippus took over from Cleanthes as the head of the Stoic school
     From: PG (Db (chronology) [2030], 0771)
157 (roughly): Carneades became head of the Academy [PG]
     Full Idea: In around 157 BCE Carneades took over as head of the Academy from Hegesinus
     From: PG (Db (chronology) [2030], 0843)
85: most philosophical activity moves to Alexandria [PG]
     Full Idea: In around 85 BCE Athens went into philosophical decline, and leadership moved to Alexandria
     From: PG (Db (chronology) [2030], 0915)
78: Cicero visited the stoic school on Rhodes [PG]
     Full Idea: In around 78 BCE Cicero visited the school of Posidonius in Rhodes.
     From: PG (Db (chronology) [2030], 0922)
60 (roughly): Lucretius wrote his Latin poem on epicureanism [PG]
     Full Idea: In around 60 BCE Lucretius wrote his Latin poem on Epicureanism
     From: PG (Db (chronology) [2030], 0940)
65: Seneca forced to commit suicide by Nero [PG]
     Full Idea: In 65 CE Seneca was forced to commit suicide by the Emperor Nero.
     From: PG (Db (chronology) [2030], 1065)
80: the discourses of the stoic Epictetus are written down [PG]
     Full Idea: In around 80 CE the 'Discourses' of the freed slave Epictetus were written down in Rome.
     From: PG (Db (chronology) [2030], 1080)
170 (roughly): Marcus Aurelius wrote his private stoic meditations [PG]
     Full Idea: In around 170 CE the Emperor Marcus Aurelius wrote his 'Meditations' for private reading.
     From: PG (Db (chronology) [2030], 1170)
-200 (roughly): Sextus Empiricus wrote a series of books on scepticism [PG]
     Full Idea: In around 200 CE Sextus Empiricus wrote a series of books (which survive) defending scepticism
     From: PG (Db (chronology) [2030], 1200)
263: Porphyry began to study with Plotinus in Rome [PG]
     Full Idea: In 263 CE Porphyry joined Plotinus' classes in Rome
     From: PG (Db (chronology) [2030], 1263)
310: Christianity became the official religion of the Roman empire [PG]
     Full Idea: In 310 CE Christianity became the official religion of the Roman Empire
     From: PG (Db (chronology) [2030], 1310)
387: Ambrose converts Augustine to Christianity [PG]
     Full Idea: In 387 CE Augustine converted to Christianity in Milan, guided by St Ambrose
     From: PG (Db (chronology) [2030], 1387)
523: Boethius imprisoned at Pavia, and begins to write [PG]
     Full Idea: In 523 CE Boethius was imprisoned in exile at Pavia, and wrote 'Consolations of Philosophy'
     From: PG (Db (chronology) [2030], 1523)
529: the emperor Justinian closes all the philosophy schools in Athens [PG]
     Full Idea: In 529 CE the Emperor Justinian closed all the philosophy schools in Athens
     From: PG (Db (chronology) [2030], 1529)
1. Philosophy / C. History of Philosophy / 3. Earlier European Philosophy / a. Earlier European chronology
622 (roughly): Mohammed writes the Koran [PG]
     Full Idea: Mohammed: In about 622 CE Muhammed wrote the basic text of Islam, the Koran.
     From: PG (Db (chronology) [2030], 1622)
642: Arabs close the philosophy schools in Alexandria [PG]
     Full Idea: In 642 CE Alexandria was captured by the Arabs, and the philosophy schools were closed
     From: PG (Db (chronology) [2030], 1642)
910 (roughly): Al-Farabi wrote Arabic commentaries on Aristotle [PG]
     Full Idea: Alfarabi: In around 910 CE Al-Farabi explained and expanded Aristotle for the Islamic world.
     From: PG (Db (chronology) [2030], 1910)
1015 (roughly): Ibn Sina (Avicenna) writes a book on Aristotle [PG]
     Full Idea: In around 1015 Avicenna produced his Platonised version of Aristotle in 'The Healing'
     From: PG (Db (chronology) [2030], 2015)
1090: Anselm publishes his proof of the existence of God [PG]
     Full Idea: Anselm: In about 1090 St Anselm of Canterbury publishes his Ontological Proof of God's existence
     From: PG (Db (chronology) [2030], 2090)
1115: Abelard is the chief logic teacher in Paris [PG]
     Full Idea: In around 1115 Abelard became established as the chief logic teacher in Paris
     From: PG (Db (chronology) [2030], 2115)
1166: Ibn Rushd (Averroes) wrote extensive commentaries on Aristotle [PG]
     Full Idea: In around 1166 Averroes (Ibn Rushd), in Seville, wrote extensive commentaries on Aristotle
     From: PG (Db (chronology) [2030], 2166)
1266: Aquinas began writing 'Summa Theologica' [PG]
     Full Idea: In 1266 Aquinas began writing his great theological work, the 'Summa Theologica'
     From: PG (Db (chronology) [2030], 2266)
1280: after his death, the teaching of Aquinas becomes official Dominican doctrine [PG]
     Full Idea: In around 1280 Aquinas's teaching became the official theology of the Dominican order
     From: PG (Db (chronology) [2030], 2280)
1328: William of Ockham decides the Pope is a heretic, and moves to Munich [PG]
     Full Idea: In 1328 William of Ockham decided the Pope was a heretic, and moved to Munich
     From: PG (Db (chronology) [2030], 2328)
1347: the Church persecutes philosophical heresies [PG]
     Full Idea: In 1347 the Church began extensive persecution of unorthodox philosophical thought
     From: PG (Db (chronology) [2030], 2347)
1470: Marsilio Ficino founds a Platonic Academy in Florence [PG]
     Full Idea: In around 1470 Marsilio Ficino founded a Platonic Academy in Florence
     From: PG (Db (chronology) [2030], 2470)
1513: Machiavelli wrote 'The Prince' [PG]
     Full Idea: In 1513 Machiavelli wrote 'The Prince', a tough view of political theory.
     From: PG (Db (chronology) [2030], 2513)
1543: Copernicus publishes his heliocentric view of the solar system [PG]
     Full Idea: In 1543 Nicholas Copernicus, a Polish monk, publishes his new theory of the solar system.
     From: PG (Db (chronology) [2030], 2543)
1580: Montaigne publishes his essays [PG]
     Full Idea: In 1580 Montaigne published a volume of his 'Essays'
     From: PG (Db (chronology) [2030], 2580)
1600: Giordano Bruno was burned at the stake in Rome [PG]
     Full Idea: In 1600 Giordano Bruno was burnt at the stake in Rome, largely for endorsing Copernicus
     From: PG (Db (chronology) [2030], 2600)
1. Philosophy / C. History of Philosophy / 4. Later European Philosophy / a. Later European chronology
1619: Descartes's famous day of meditation inside a stove [PG]
     Full Idea: In 1619 Descartes had a famous day of meditation in a heated stove at Ulm
     From: PG (Db (chronology) [2030], 2619)
1620: Bacon publishes 'Novum Organum' [PG]
     Full Idea: Francis Bacon: In 1620 Bacon published his 'Novum Organon', urging the rise of experimental science
     From: PG (Db (chronology) [2030], 2620)
1633: Galileo convicted of heresy by the Inquisition [PG]
     Full Idea: In 1633 Galileo was condemned to life emprisonment for contradicting church teachings.
     From: PG (Db (chronology) [2030], 2633)
1641: Descartes publishes his 'Meditations' [PG]
     Full Idea: In 1641 Descartes published his well-known 'Meditations', complete with Objections and Replies
     From: PG (Db (chronology) [2030], 2641)
1650: death of Descartes, in Stockholm [PG]
     Full Idea: In 1650 Descartes died in Stockholm, after stressful work for Queen Christina
     From: PG (Db (chronology) [2030], 2650)
1651: Hobbes publishes 'Leviathan' [PG]
     Full Idea: In 1651 Hobbes published his great work on politics and contract morality, 'Leviathan'
     From: PG (Db (chronology) [2030], 2651)
1662: the Port Royal Logic is published [PG]
     Full Idea: Antoine Arnauld: In 1662 Arnauld and Nicole published their famous text, the 'Port-Royal Logic'
     From: PG (Db (chronology) [2030], 2662)
1665: Spinoza writes his 'Ethics' [PG]
     Full Idea: In 1665 the first draft of Spinoza's 'Ethics', his major work, was finished, and published posthumously
     From: PG (Db (chronology) [2030], 2665)
1676: Leibniz settled as librarian to the Duke of Brunswick [PG]
     Full Idea: In 1676 Leibniz became librarian to the Duke of Brunswick, staying for the rest of his life
     From: PG (Db (chronology) [2030], 2676)
1687: Newton publishes his 'Principia Mathematica' [PG]
     Full Idea: In 1687 Newton published his 'Principia', containing his theory of gravity.
     From: PG (Db (chronology) [2030], 2687)
1690: Locke publishes his 'Essay' [PG]
     Full Idea: In 1690 Locke published his 'Essay', his major work on empiricism
     From: PG (Db (chronology) [2030], 2690)
1697: Bayle publishes his 'Dictionary' [PG]
     Full Idea: Pierre Bayle: In about 1697 Pierre Bayle published his 'Historical and Critical Dictionary'
     From: PG (Db (chronology) [2030], 2697)
1713: Berkeley publishes his 'Three Dialogues' [PG]
     Full Idea: In 1713 Berkeley published a popular account of his empiricist idealism in 'Three Dialogues'
     From: PG (Db (chronology) [2030], 2713)
1734: Voltaire publishes his 'Philosophical Letters' [PG]
     Full Idea: Francois-Marie Voltaire: In 1734 Voltaire's 'Lettres Philosophiques' praised liberalism and empiricism
     From: PG (Db (chronology) [2030], 2734)
1739: Hume publishes his 'Treatise' [PG]
     Full Idea: In 1739 Hume returned to Edinburgh and published his 'Treatise', but it sold very few copies
     From: PG (Db (chronology) [2030], 2739)
1762: Rousseau publishes his 'Social Contract' [PG]
     Full Idea: In 1762 Rousseau published his 'Social Contract', basing politics on the popular will
     From: PG (Db (chronology) [2030], 2762)
1781: Kant publishes his 'Critique of Pure Reason' [PG]
     Full Idea: In 1781 Kant published his first great work, the 'Critique of Pure Reason'
     From: PG (Db (chronology) [2030], 2781)
1785: Reid publishes his essays defending common sense [PG]
     Full Idea: In 1785 Thomas Reid, based in Glasgow, published essays defending common sense.
     From: PG (Db (chronology) [2030], 2785)
1798: the French Revolution [PG]
     Full Idea: In 1789 the French Revolution gave strong impetus to the anti-rational 'Romantic' movement
     From: PG (Db (chronology) [2030], 2789)
1807: Hegel publishes his 'Phenomenology of Spirit' [PG]
     Full Idea: In 1807 Hegel published his first major work, the 'Phenomenology of Spirit'
     From: PG (Db (chronology) [2030], 2807)
1818: Schopenhauer publishes his 'World as Will and Idea' [PG]
     Full Idea: In 1818 Schopenhauer published 'The World as Will and Idea', his major work
     From: PG (Db (chronology) [2030], 2818)
1840: Kierkegaard is writing extensively in Copenhagen [PG]
     Full Idea: In around 1840 Kierkegaard lived a quiet life as a writer in Copenhagen
     From: PG (Db (chronology) [2030], 2840)
1843: Mill publishes his 'System of Logic' [PG]
     Full Idea: In 1843 Mill published his 'System of Logic'
     From: PG (Db (chronology) [2030], 2843)
1848: Marx and Engels publis the Communist Manifesto [PG]
     Full Idea: Karl Marx: In 1848 Marx and Engels published their 'Communist Manifesto'
     From: PG (Db (chronology) [2030], 2848)
1859: Darwin publishes his 'Origin of the Species' [PG]
     Full Idea: Charles Darwin: In 1859 Charles Darwin published his theory of natural selection in 'Origin of the Species'.
     From: PG (Db (chronology) [2030], 2859)
1861: Mill publishes 'Utilitarianism' [PG]
     Full Idea: In 1861 Mill published his book 'Utilitarianism'
     From: PG (Db (chronology) [2030], 2861)
1867: Marx begins publishing 'Das Kapital' [PG]
     Full Idea: Karl Marx: In 1867 Karl Marx began publishing his political work 'Das Kapital'
     From: PG (Db (chronology) [2030], 2867)
1. Philosophy / C. History of Philosophy / 5. Modern Philosophy / a. Modern philosophy chronology
1879: Peirce taught for five years at Johns Hopkins University [PG]
     Full Idea: In 1879 Peirce began five years of teaching at Johns Hopkins University
     From: PG (Db (chronology) [2030], 2879)
1879: Frege invents predicate logic [PG]
     Full Idea: In 1879 Frege published his 'Concept Script', which created predicate logic
     From: PG (Db (chronology) [2030], 2879)
1892: Frege's essay 'Sense and Reference' [PG]
     Full Idea: In 1892 Frege published his famous essay 'Sense and Reference' (Sinn und Bedeutung)
     From: PG (Db (chronology) [2030], 2882)
1884: Frege publishes his 'Foundations of Arithmetic' [PG]
     Full Idea: In 1884 Frege published his 'Foundations of Arithmetic', the beginning of logicism
     From: PG (Db (chronology) [2030], 2884)
1885: Nietzsche completed 'Thus Spake Zarathustra' [PG]
     Full Idea: In about 1885 Nietzsche completed his book 'Also Sprach Zarathustra'
     From: PG (Db (chronology) [2030], 2885)
1888: Dedekind publishes axioms for arithmetic [PG]
     Full Idea: In 1888 Dedekind created simple axioms for arithmetic (the Peano Axioms)
     From: PG (Db (chronology) [2030], 2888)
1890: James published 'Principles of Psychology' [PG]
     Full Idea: In 1890 James published his 'Principles of Psychology'
     From: PG (Db (chronology) [2030], 2890)
1895 (roughly): Freud developed theories of the unconscious [PG]
     Full Idea: In around 1895 Sigmund Freud developed his theories of the unconscious mind
     From: PG (Db (chronology) [2030], 2895)
1900: Husserl began developing Phenomenology [PG]
     Full Idea: In 1900 Edmund Husserl began presenting his new philosophy of Phenomenology
     From: PG (Db (chronology) [2030], 2900)
1903: Moore published 'Principia Ethica' [PG]
     Full Idea: In 1903 G.E. Moore published his 'Principia Ethica', attacking naturalistic ethics.
     From: PG (Db (chronology) [2030], 2903)
1904: Dewey became professor at Columbia University [PG]
     Full Idea: In 1904 Dewey moved to Columbia University in New York.
     From: PG (Db (chronology) [2030], 2904)
1908: Zermelo publishes axioms for set theory [PG]
     Full Idea: In 1908 Zermelo published an axiomatisation of the new set theory
     From: PG (Db (chronology) [2030], 2908)
1910: Russell and Whitehead begin publishing 'Principia Mathematica' [PG]
     Full Idea: In 1910 Russell began publication of 'Principia Mathematica', with Whitehead
     From: PG (Db (chronology) [2030], 2910)
1912: Russell meets Wittgenstein in Cambridge [PG]
     Full Idea: In 1912 Russell met Wittgenstein at Cambridge
     From: PG (Db (chronology) [2030], 2912)
1921: Wittgenstein's 'Tractatus' published [PG]
     Full Idea: In 1921 Wittgenstein's 'Tractatus' was published
     From: PG (Db (chronology) [2030], 2921)
1927: Heidegger's 'Being and Time' published [PG]
     Full Idea: In 1927 Heidegger's major work, 'Being and Time', was published
     From: PG (Db (chronology) [2030], 2927)
1930: Frank Ramsey dies at 27 [PG]
     Full Idea: In 1930 Frank Ramsey died at the age of 27.
     From: PG (Db (chronology) [2030], 2930)
1931: Gödel's Incompleteness Theorems [PG]
     Full Idea: Kurt Gödel: In 1931 the mathematician Kurt Gödel publishes his Incompleteness Theorems.
     From: PG (Db (chronology) [2030], 2931)
1933: Tarski's theory of truth [PG]
     Full Idea: Alfred Tarski: In 1933 Alfred Tarski wrote a famous paper presenting a semantic theory of truth.
     From: PG (Db (chronology) [2030], 2933)
1942: Camus published 'The Myth of Sisyphus' [PG]
     Full Idea: In 1942 Camus published 'The Myth of Sisyphus', exploring suicide and the absurd
     From: PG (Db (chronology) [2030], 2942)
1943: Sartre's 'Being and Nothingness' [PG]
     Full Idea: In 1943 Jean-Paul Sartre published his major work, 'Being and Nothingness'
     From: PG (Db (chronology) [2030], 2943)
1945: Merleau-Ponty's 'Phenomenology of Perception' [PG]
     Full Idea: Maurice Merleau-Ponty: In 1945 Maurice Merleau-Pont published 'The Phenomenology of Perception'
     From: PG (Db (chronology) [2030], 2945)
1947: Carnap published 'Meaning and Necessity' [PG]
     Full Idea: In 1947 Carnap published 'Meaning and Necessity'
     From: PG (Db (chronology) [2030], 2947)
1950: Quine's essay 'Two Dogmas of Empiricism' [PG]
     Full Idea: In 1950 Willard Quine published 'Two Dogmas of Empiricism', attacking analytic truth
     From: PG (Db (chronology) [2030], 2950)
1953: Wittgenstein's 'Philosophical Investigations' [PG]
     Full Idea: In 1953 Wittgenstein's posthumous work 'Philosophical Investigations' is published
     From: PG (Db (chronology) [2030], 2953)
1956: Place proposed mind-brain identity [PG]
     Full Idea: In 1956 U.T. Place proposed that the mind is identical to the brain
     From: PG (Db (chronology) [2030], 2956)
1962: Kuhn's 'Structure of Scientific Revolutions' [PG]
     Full Idea: In 1962 Thomas Kuhn's 'Structure of Scientific Revolutions' questioned the authority of science
     From: PG (Db (chronology) [2030], 2962)
1967: Putnam proposed functionalism of the mind [PG]
     Full Idea: In 1967 Putname proposed the functionalist view of the mind
     From: PG (Db (chronology) [2030], 2967)
1971: Rawls's 'A Theory of Justice' [PG]
     Full Idea: In 1971 John Rawls published his famous defence of liberalism in 'A Theory of Justice'
     From: PG (Db (chronology) [2030], 2971)
1972: Kripke publishes 'Naming and Necessity' [PG]
     Full Idea: In 1972 Saul Kripke's 'Naming and Necessity' revised theories about language and reality
     From: PG (Db (chronology) [2030], 2972)
1975: Singer publishes 'Animal Rights' [PG]
     Full Idea: Peter Singer: In 1975 Peter Singer's 'Animal Rights' turned the attention of philosophers to applied ethics.
     From: PG (Db (chronology) [2030], 2975)
1975: Putnam published his Twin Earth example [PG]
     Full Idea: In 1975 Putnam published 'The Meaning of 'Meaning'', containing his Twin Earth example
     From: PG (Db (chronology) [2030], 2975)
1986: David Lewis publishes 'On the Plurality of Worlds' [PG]
     Full Idea: In 1986 David Lewis published 'On the Plurality of Worlds', about possible worlds.
     From: PG (Db (chronology) [2030], 2986)
1. Philosophy / E. Nature of Metaphysics / 5. Metaphysics beyond Science
Some say metaphysics is a highly generalised empirical study of objects [Tarski]
     Full Idea: For some people metaphysics is a general theory of objects (ontology) - a discipline which is to be developed in a purely empirical way, and which differs from other empirical disciplines in its generality.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 19)
     A reaction: Tarski says some people despise it, but for him such metaphysics is 'not objectionable'. I subscribe to this view, but the empirical aspect is very remote, because it's too general for detail observation or experiment. Generality is the key to philosophy.
1. Philosophy / E. Nature of Metaphysics / 6. Metaphysics as Conceptual
Modern empirical metaphysics focuses on ontological commitments of discourse, or on presuppositions [Loux/Zimmerman]
     Full Idea: The empiricist revival of metaphysics came with Quine, who focused on ontological commitments associated with accepting a body of discourse, and Strawson, asking about the presuppositions of our conceptual practices.
     From: M Loux / D Zimmerman (Intro to Oxford Hndbk of Metaphysics [2003])
     A reaction: I find myself preferring the British approach. I can discourse about things without ontological commitment, and utter truths about non-existent things. I really yearn, though, for the third way - actually reasoning towards knowing what's out there.
1. Philosophy / F. Analytic Philosophy / 1. Nature of Analysis
Disputes that fail to use precise scientific terminology are all meaningless [Tarski]
     Full Idea: Disputes like the vague one about 'the right conception of truth' occur in all domains where, instead of exact, scientific terminology, common language with its vagueness and ambiguity is used; and they are always meaningless, and therefore in vain.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 14)
     A reaction: Taski taught a large number of famous philosophers in California in the 1950s, and this approach has had a huge influence. Recently there has been a bit of a rebellion. E.g. Kit Fine doesn't think it can all be done in formal languages.
1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
Note that "is" can assert existence, or predication, or identity, or classification [PG]
     Full Idea: There are four uses of the word "is" in English: as existence ('he is at home'), as predication ('he is tall'), as identity ('he is the man I saw'), and as classification ('he is British').
     From: PG (Db (ideas) [2031])
     A reaction: This seems a nice instance of the sort of point made by analytical philosophy, which can lead to horrible confusion in other breeds of philosophy when it is overlooked.
2. Reason / D. Definition / 1. Definitions
For a definition we need the words or concepts used, the rules, and the structure of the language [Tarski]
     Full Idea: We must specify the words or concepts which we wish to use in defining the notion of truth; and we must also give the formal rules to which the definition should conform. More generally, we must describe the formal structure of the language.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 01)
     A reaction: This, of course, is a highly formal view of how definition should be achieved, offered in anticipation of one of the most famous definitions in logic (of truth, by Tarski). Normally we assume English and classical logic.
2. Reason / F. Fallacies / 1. Fallacy
Fallacies are errors in reasoning, 'formal' if a clear rule is breached, and 'informal' if more general [PG]
     Full Idea: Fallacies are errors in reasoning, labelled as 'formal' if a clear rule has been breached, and 'informal' if some less precise error has been made.
     From: PG (Db (ideas) [2031])
     A reaction: Presumably there can be a grey area between the two.
2. Reason / F. Fallacies / 3. Question Begging
Question-begging assumes the proposition which is being challenged [PG]
     Full Idea: To beg the question is to take for granted in your argument that very proposition which is being challenged
     From: PG (Db (ideas) [2031])
     A reaction: An undoubted fallacy, and a simple failure to engage in the rational enterprise. I suppose one might give a reason for something, under the mistaken apprehension that it didn't beg the question; analysis of logical form is then needed.
2. Reason / F. Fallacies / 6. Fallacy of Division
What is true of a set is also true of its members [PG]
     Full Idea: The fallacy of division is the claim that what is true of a set must therefore be true of its members.
     From: PG (Db (ideas) [2031])
     A reaction: Clearly a fallacy, but if you only accept sets which are rational, then there is always a reason why a particular is a member of a set, and you can infer facts about particulars from the nature of the set
2. Reason / F. Fallacies / 7. Ad Hominem
The Ad Hominem Fallacy criticises the speaker rather than the argument [PG]
     Full Idea: The Ad Hominem Fallacy is to criticise the person proposing an argument rather than the argument itself, as when you say "You would say that", or "Your behaviour contradicts what you just said".
     From: PG (Db (ideas) [2031])
     A reaction: Nietzsche is very keen on ad hominem arguments, and cheerfully insults great philosophers, but then he doesn't believe there is such a thing as 'pure argument', and he is a relativist.
3. Truth / A. Truth Problems / 2. Defining Truth
Tarski proved that truth cannot be defined from within a given theory [Tarski, by Halbach]
     Full Idea: Tarski's Theorem states that under fairly generally applicable conditions, the assumption that there is a definition of truth within a given theory for the language of that same theory leads to a contradiction.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 1
     A reaction: That might leave room for a definition outside the given theory. I take the main motivation for the axiomatic approach to be a desire to get a theory of truth within the given theory, where Tarski's Theorem says traditional approaches are just wrong.
Tarski proved that any reasonably expressive language suffers from the liar paradox [Tarski, by Horsten]
     Full Idea: Tarski's Theorem on the undefinability of truth says in a language sufficiently rich to talk about itself (which Gödel proved possible, via coding) the liar paradox can be carried out.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Leon Horsten - The Tarskian Turn 02.2
     A reaction: The point is that truth is formally indefinable if it leads inescapably to contradiction, which the liar paradox does. This theorem is the motivation for all modern attempts to give a rigorous account of truth.
'True sentence' has no use consistent with logic and ordinary language, so definition seems hopeless [Tarski]
     Full Idea: The possibility of a consistent use of 'true sentence' which is in harmony with the laws of logic and the spirit of everyday language seems to be very questionable, so the same doubt attaches to the possibility of constructing a correct definition.
     From: Alfred Tarski (The Concept of Truth for Formalized Languages [1933], §1)
     A reaction: This is often cited as Tarski having conclusively proved that 'true' cannot be defined from within a language, but his language here is much more circumspect. Modern critics say the claim depends entirely on classical logic.
In everyday language, truth seems indefinable, inconsistent, and illogical [Tarski]
     Full Idea: In everyday language it seems impossible to define the notion of truth or even to use this notion in a consistent manner and in agreement with the laws of logic.
     From: Alfred Tarski (works [1936]), quoted by Feferman / Feferman - Alfred Tarski: life and logic Int III
     A reaction: [1935] See Logic|Theory of Logic|Semantics of Logic for Tarski's approach to truth.
Definitions of truth should not introduce a new version of the concept, but capture the old one [Tarski]
     Full Idea: The desired definition of truth does not aim to specify the meaning of a familiar word used to denote a novel notion; on the contrary, it aims to catch hold of the actual meaning of an old notion.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 01)
     A reaction: Tarski refers back to Aristotle for an account of the 'old notion'. To many the definition of Tarski looks very weird, so it is important to see that he is trying to capture the original concept.
A definition of truth should be materially adequate and formally correct [Tarski]
     Full Idea: The main problem of the notion of truth is to give a satisfactory definition which is materially adequate and formally correct.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 01)
     A reaction: That is, I take it, that it covers all cases of being true and failing to be true, and it fits in with the logic. The logic is explicitly classical logic, and he is not aiming to give the 'nature' or natural language understanding of the concept.
A rigorous definition of truth is only possible in an exactly specified language [Tarski]
     Full Idea: The problem of the definition of truth obtains a precise meaning and can be solved in a rigorous way only for those languages whose structure has been exactly specified.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 06)
     A reaction: Taski has just stated how to exactly specify the structure of a language. He says definition can only be vague and approximate for natural languages. (The usual criticism of the correspondence theory is its vagueness).
We may eventually need to split the word 'true' into several less ambiguous terms [Tarski]
     Full Idea: A time may come when we find ourselves confronted with several incompatible, but equally clear and precise, conceptions of truth. It will then become necessary to abandon the ambiguous usage of the word 'true', and introduce several terms instead.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 14)
     A reaction: There may be a whiff of the pragmatic attitude to truth here, though that view is not necessarily pluralist. Analytic philosophy needs much more splitting of difficult terms into several more focused terms.
3. Truth / C. Correspondence Truth / 3. Correspondence Truth critique
Tarski's Theorem renders any precise version of correspondence impossible [Tarski, by Halbach]
     Full Idea: Tarski's Theorem applies to any sufficient precise version of the correspondence theory of truth, and all the other traditional theories of truth.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 1
     A reaction: This is the key reason why modern thinkers have largely dropped talk of the correspondence theory. See Idea 16295.
3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
Tarskian semantics says that a sentence is true iff it is satisfied by every sequence [Tarski, by Hossack]
     Full Idea: Tarskian semantics says that a sentence is true iff it is satisfied by every sequence, where a sequence is a set-theoretic individual, a set of ordered pairs each with a natural number as its first element and an object from the domain for its second.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Keith Hossack - Plurals and Complexes 3
'"It is snowing" is true if and only if it is snowing' is a partial definition of the concept of truth [Tarski]
     Full Idea: Statements of the form '"it is snowing" is true if and only if it is snowing' and '"the world war will begin in 1963" is true if and only if the world war will being in 1963' can be regarded as partial definitions of the concept of truth.
     From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.404)
     A reaction: The key word here is 'partial'. Truth is defined, presumably, when every such translation from the object language has been articulated, which is presumably impossible, given the infinity of concatenated phrases possible in a sentence.
Tarski gave up on the essence of truth, and asked how truth is used, or how it functions [Tarski, by Horsten]
     Full Idea: Tarski emancipated truth theory from traditional philosophy, by no longer posing Pilate's question (what is truth? or what is the essence of truth?) but instead 'how is truth used?', 'how does truth function?' and 'how can its functioning be described?'.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Leon Horsten - The Tarskian Turn 02.2
     A reaction: Horsten, later in the book, does not give up on the essence of truth, and modern theorists are trying to get back to that question by following Tarski's formal route. Modern analytic philosophy at its best, it seems to me.
Tarski did not just aim at a definition; he also offered an adequacy criterion for any truth definition [Tarski, by Halbach]
     Full Idea: Tarski did not settle for a definition of truth, taking its adequacy for granted. Rather he proposed an adequacy criterion for evaluating the adequacy of definitions of truth. The criterion is his famous Convention T.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 3
     A reaction: Convention T famously says the sentence is true if and only if a description of the sentence is equivalent to affirming the sentence. 'Snow is white' iff snow is white.
Tarski enumerates cases of truth, so it can't be applied to new words or languages [Davidson on Tarski]
     Full Idea: Tarski does not tell us how to apply his concept of truth to a new case, whether the new case is a new language or a word newly added to a language. This is because enumerating cases gives no clue for the next or general case.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Donald Davidson - Truth and Predication 1
     A reaction: His account has been compared to a telephone directory. We aim to understand the essence of anything, so that we can fully know it, and explain and predict how it will behave. Either truth is primitive, or I demand to know its essence.
Tarski define truths by giving the extension of the predicate, rather than the meaning [Davidson on Tarski]
     Full Idea: Tarski defined the class of true sentences by giving the extension of the truth predicate, but he did not give the meaning.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Donald Davidson - Truth and Predication 1
     A reaction: This is analogous to giving an account of the predicate 'red' as the set of red objects. Since I regard that as a hopeless definition of 'red', I am inclined to think the same of Tarski's account of truth. It works in the logic, but so what?
Tarski made truth relative, by only defining truth within some given artificial language [Tarski, by O'Grady]
     Full Idea: Tarski's account doesn't hold for natural languages. The general notion of truth is replaced by "true-in-L", where L is a formal language. Hence truth is relativized to each artificial language.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Paul O'Grady - Relativism Ch.2
     A reaction: This is a pretty good indication that Tarski's theory is NOT a correspondence theory, even if its structure may sometimes give that impression.
Tarski has to avoid stating how truths relate to states of affairs [Kirkham on Tarski]
     Full Idea: Tarski has to define truths so as not to make explicit the relation between a true sentence and an obtaining state of affairs. ...He has to list each sentence separately, and simply assign it a state of affairs.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Richard L. Kirkham - Theories of Truth: a Critical Introduction 5.8
     A reaction: He has to avoid semantic concepts like 'reference', because he wants a physicalist theory, according to Kirkham. Thus the hot interest in theories of reference in the 1970s/80s. And also attempts to give a physicalist account of meaning.
It is convenient to attach 'true' to sentences, and hence the language must be specified [Tarski]
     Full Idea: For several reasons it appears most convenient to apply the term 'true' to sentences, and we shall follow this course. Consequently, we must always relate the notion of truth, like that of a sentence, to a specific language.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 02)
     A reaction: Personally I take truth to attach to propositions, since sentences are ambiguous. In Idea 17308 the one sentence expresses three different truths (in my opinion), even though a single sentence (given in the object language) specifies it.
In the classical concept of truth, 'snow is white' is true if snow is white [Tarski]
     Full Idea: If we base ourselves on the classical conception of truth, we shall say that the sentence 'snow is white' is true if snow is white, and it is false if snow is not white.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 04)
     A reaction: I had not realised, prior to his, how closely Tarski is sticking to Aristotle's famous formulation of truth. The point is that you can only specify 'what is' using a language. Putting 'true' in the metalanguage gives specific content to Aristotle.
Scheme (T) is not a definition of truth [Tarski]
     Full Idea: It is a mistake to regard scheme (T) as a definition of truth.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 15)
     A reaction: The point is, I take it, that the definition is the multitude of sentences which are generated by the schema, not the schema itself.
Each interpreted T-sentence is a partial definition of truth; the whole definition is their conjunction [Tarski]
     Full Idea: In 'X is true iff p' if we replace X by the name of a sentence and p by a particular sentence this can be considered a partial definition of truth. The whole definition has to be ...a logical conjunction of all these partial definitions.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 04)
     A reaction: This seems an unprecedented and odd way to define something. Define 'red' by '"This tomato is red" iff this tomato is red', etc? Define 'stone' by collecting together all the stones? The complex T-sentences are infinite in number.
Use 'true' so that all T-sentences can be asserted, and the definition will then be 'adequate' [Tarski]
     Full Idea: We wish to use the term 'true' in such a way that all the equivalences of the form (T) [i.e. X is true iff p] can be asserted, and we shall call a definition of truth 'adequate' if all these equivalences follow from it.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 04)
     A reaction: The interpretation of Tarski's theory is difficult. From this I'm thinking that 'true' is simply being defined as 'assertible'. This is the status of each line in a logical proof, if there is a semantic dimension to the proof (and not mere syntax).
We don't give conditions for asserting 'snow is white'; just that assertion implies 'snow is white' is true [Tarski]
     Full Idea: Semantic truth implies nothing regarding the conditions under which 'snow is white' can be asserted. It implies only that, whenever we assert or reject this sentence, we must be ready to assert or reject the correlated sentence '"snow is white" is true'.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 18)
     A reaction: This appears to identify truth with assertibility, which is pretty much what modern pragmatists say. How do you distinguish 'genuine' assertion from rhetorical, teasing or lying assertions? Genuine assertion implies truth? Hm.
3. Truth / F. Semantic Truth / 1. Tarski's Truth / b. Satisfaction and truth
Truth only applies to closed formulas, but we need satisfaction of open formulas to define it [Burgess on Tarski]
     Full Idea: In Tarski's theory of truth, although the notion of truth is applicable only to closed formulas, to define it we must define a more general notion of satisfaction applicable to open formulas.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by John P. Burgess - Philosophical Logic 1.8
     A reaction: This is a helpful pointer to what is going on in the Tarski definition. It culminates in the 'satisfaction of all sequences', which presumable delivers the required closed formula.
Tarski uses sentential functions; truly assigning the objects to variables is what satisfies them [Tarski, by Rumfitt]
     Full Idea: Tarski invoked the notion of a sentential function, where components are replaced by appropriate variables. A function is then satisfied by assigning objects to variables. An assignment satisfies if the function is true of the things assigned.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Ian Rumfitt - The Boundary Stones of Thought 3.2
     A reaction: [very compressed] This use of sentential functions, rather than sentences, looks like the key to Tarski's definition of truth.
We can define the truth predicate using 'true of' (satisfaction) for variables and some objects [Tarski, by Horsten]
     Full Idea: The truth predicate, says Tarski, should be defined in terms of the more primitive satisfaction relation: the relation of being 'true of'. The fundamental notion is a formula (containing the free variables) being true of a sequence of objects as values.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Leon Horsten - The Tarskian Turn 06.3
For physicalism, reduce truth to satisfaction, then define satisfaction as physical-plus-logic [Tarski, by Kirkham]
     Full Idea: Tarski, a physicalist, reduced semantics to physical and/or logicomathematical concepts. He defined all semantic concepts, save satisfaction, in terms of truth. Then truth is defined in terms of satisfaction, and satisfaction is given non-semantically.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Richard L. Kirkham - Theories of Truth: a Critical Introduction 5.1
     A reaction: The term 'logicomathematical' is intended to cover set theory. Kirkham says you can remove these restrictions from Tarski's theory, and the result is a version of the correspondence theory.
Insight: don't use truth, use a property which can be compositional in complex quantified sentence [Tarski, by Kirkham]
     Full Idea: Tarski's great insight is find another property, since open sentences are not truth. It must be had by open and genuine sentences. Clauses having it must generate it for the whole sentence. Truth can be defined for sentences by using it.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Richard L. Kirkham - Theories of Truth: a Critical Introduction 5.4
     A reaction: The proposed property is 'satisfaction', which can (unlike truth) be a feature open sentences (such as 'x is green', which is satisfied by x='grass'),
Tarski gave axioms for satisfaction, then derived its explicit definition, which led to defining truth [Tarski, by Davidson]
     Full Idea: Tarski turned his axiomatic characterisation of satisfaction into an explicit definition of the satisfaction-predicate using some fancy set theoretical apparatus, and this in turn leads to the explicit definition of the truth predicate.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Donald Davidson - Truth and Predication 7
The best truth definition involves other semantic notions, like satisfaction (relating terms and objects) [Tarski]
     Full Idea: It turns out that the simplest and most natural way of obtaining an exact definition of truth is one which involves the use of other semantic notions, e.g. the notion of satisfaction (...which expresses relations between expressions and objects).
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 05)
     A reaction: While the T-sentences appear to be 'minimal' and 'deflationary', it seems important to remember that 'satisfaction', which is basic to his theory, is a very robust notion. He actually mentions 'objects'. But see Idea 19185.
Specify satisfaction for simple sentences, then compounds; true sentences are satisfied by all objects [Tarski]
     Full Idea: To define satisfaction we indicate which objects satisfy the simplest sentential functions, then state the conditions for compound functions. This applies automatically to sentences (with no free variables) so a true sentence is satisfied by all objects.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 11)
     A reaction: I presume nothing in the domain of objects can conflict with a sentence that has been satisfied by some of them, so 'all' the objects satisfy the sentence. Tarski doesn't use the word 'domain'. Basic satisfaction seems to be stipulated.
3. Truth / F. Semantic Truth / 1. Tarski's Truth / c. Meta-language for truth
We can't use a semantically closed language, or ditch our logic, so a meta-language is needed [Tarski]
     Full Idea: In a 'semantically closed' language all sentences which determine the adequate usage of 'true' can be asserted in the language. ...We can't change our logic, so we reject such languages. ...So must use two different languages to discuss truth.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 08-09)
     A reaction: This section explains why a meta-language is required. It rests entirely on the existence of the Liar paradox is a semantically closed language.
The metalanguage must contain the object language, logic, and defined semantics [Tarski]
     Full Idea: Every sentence which occurs in the object language must also occur in the metalanguage, or can be translated into the metalanguage. There must also be logical terms, ...and semantic terms can only be introduced in the metalanguage by definition.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 09)
     A reaction: He suggest that if the languages are 'typed', the meta-languag, to be 'richer', must contain variables of a higher logica type. Does this mean second-order logic?
3. Truth / F. Semantic Truth / 2. Semantic Truth
Tarski defined truth for particular languages, but didn't define it across languages [Davidson on Tarski]
     Full Idea: Tarski defined various predicates of the form 's is true in L', each applicable to a single language, but he failed to define a predicate of the form 's is true in L' for variable 'L'.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Donald Davidson - Truth and Predication 1
     A reaction: You might say that no one defines 'tree' to be just 'in English', but we might define 'multiplies' to be in Peano Arithmetic. This indicates the limited and formal nature of what Tarski was trying to achieve.
Tarski didn't capture the notion of an adequate truth definition, as Convention T won't prove non-contradiction [Halbach on Tarski]
     Full Idea: Every really adequate theory of truth should also prove the law of non-contradiction. Therefore Tarski's notion of adequacy in Convention T fails to capture the intuitive notion of adequacy he is after.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 3
     A reaction: Tarski points out this weakness, in a passage quoted by Halbach. This obviously raises the question of what truth theories should prove, and this is explored by Halbach. If they start to prove arithmetic, we get nervous. Non-contradiction and x-middle?
Tarski says that his semantic theory of truth is completely neutral about all metaphysics [Tarski, by Haack]
     Full Idea: Tarski says "we may remain naďve realists or idealists, empiricists or metaphysicians… The semantic conception is completely neutral toward all these issues."
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Susan Haack - Philosophy of Logics 7.5
Physicalists should explain reference nonsemantically, rather than getting rid of it [Tarski, by Field,H]
     Full Idea: Tarski work was to persuade physicalist that eliminating semantics was on the wrong track, and that we should explicate notions in the theory of reference nonsemantically rather than simply get rid of them.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Hartry Field - Tarski's Theory of Truth §3
A physicalist account must add primitive reference to Tarski's theory [Field,H on Tarski]
     Full Idea: We need to add theories of primitive reference to Tarski's account if we are to establish the notion of truth as a physicalistically acceptable notion.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Hartry Field - Tarski's Theory of Truth §4
     A reaction: This is the main point of Field's paper, and sounds very plausible to me. There is something major missing from Tarski, and at some point there needs to be a 'primitive' notion of thought and language making contact with the world, as it can't be proved.
If listing equivalences is a reduction of truth, witchcraft is just a list of witch-victim pairs [Field,H on Tarski]
     Full Idea: By similar standards of reduction to Tarski's, one might prove witchcraft compatible with physicalism, as long as witches cast only a finite number of spells. We merely list witch-and-victim pairs, with no mention of the terms of witchcraft theory.
     From: comment on Alfred Tarski (The Semantic Conception of Truth [1944], 04) by Hartry Field - Tarski's Theory of Truth §4
Tarski made truth respectable, by proving that it could be defined [Tarski, by Halbach]
     Full Idea: Tarski's proof of the definability of truth allowed him to establish truth as a respectable notion by his standards.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 3
Tarski had a theory of truth, and a theory of theories of truth [Tarski, by Read]
     Full Idea: Besides a theory of truth of his own, Tarski developed a theory of theories of truth.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Stephen Read - Thinking About Logic Ch.1
     A reaction: The famous snow biconditional is the latter, and the recursive account based on satisfaction is the former.
Tarski's 'truth' is a precise relation between the language and its semantics [Tarski, by Walicki]
     Full Idea: Tarski's analysis of the concept of 'truth' ...is given a precise treatment as a particular relation between syntax (language) and semantics (the world).
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Michal Walicki - Introduction to Mathematical Logic History E.1
     A reaction: My problem is that the concept of truth seems to apply to animal minds, which are capable of making right or wrong judgements, and of realising their errors. Tarski didn't make universal claims for his account.
Tarskian truth neglects the atomic sentences [Mulligan/Simons/Smith on Tarski]
     Full Idea: The Tarskian account of truth neglects the atomic sentences.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Mulligan/Simons/Smith - Truth-makers §1
     A reaction: Yes! The whole Tarskian edifice is built on a foundation which it is taboo even to mention. If truth is just the assignment of 'T' and 'F', that isn't even the beginnings of a theory of 'truth'.
3. Truth / G. Axiomatic Truth / 1. Axiomatic Truth
Tarski's had the first axiomatic theory of truth that was minimally adequate [Tarski, by Horsten]
     Full Idea: Tarski's work is the earliest axiomatic theory of truth that meets minimal adequacy conditions.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Leon Horsten - The Tarskian Turn 01.1
     A reaction: This shows a way in which Tarski gave a new direction to the study of truth. Subsequent theories have been 'stronger'.
Tarski defined truth, but an axiomatisation can be extracted from his inductive clauses [Tarski, by Halbach]
     Full Idea: Tarski preferred a definition of truth, but from that an axiomatisation can be extracted. His induction clauses can be turned into axioms. Hence he opened the way to axiomatic theories of truth.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 3
Tarski thought axiomatic truth was too contingent, and in danger of inconsistencies [Tarski, by Davidson]
     Full Idea: Tarski preferred an explicit definition of truth to axioms. He says axioms have a rather accidental character, only a definition can guarantee the continued consistency of the system, and it keeps truth in harmony with physical science and physicalism.
     From: report of Alfred Tarski (works [1936]) by Donald Davidson - Truth and Predication 2 n2
     A reaction: Davidson's summary, gleaned from various sources in Tarski. A big challenge for modern axiom systems is to avoid inconsistency, which is extremely hard to do (given that set theory is not sure of having achieved it).
We need an undefined term 'true' in the meta-language, specified by axioms [Tarski]
     Full Idea: We have to include the term 'true', or some other semantic term, in the list of undefined terms of the meta-language, and to express fundamental properties of the notion of truth in a series of axioms.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 10)
     A reaction: It sounds as if Tarski semantic theory gives truth for the object language, but then an axiomatic theory of truth is also needed for the metalanguage. Halbch and Horsten seem to want an axiomatic theory in the object language.
3. Truth / H. Deflationary Truth / 1. Redundant Truth
Truth can't be eliminated from universal claims, or from particular unspecified claims [Tarski]
     Full Idea: Truth can't be eliminated from universal statements saying all sentences of a certain type are true, or from the proof that 'all consequences of true sentences are true'. It is also needed if we can't name the sentence ('Plato's first sentence is true').
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 16)
     A reaction: This points to the deflationary view of truth, if its only role is in talking about other sentences in this way. Tarski gives the standard reason for rejecting the Redundancy view.
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
Semantics is a very modest discipline which solves no real problems [Tarski]
     Full Idea: Semantics as it is conceived in this paper is a sober and modest discipline which has no pretensions to being a universal patent-medicine for all the ills and diseases of mankind, whether imaginary or real.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 05)
     A reaction: Written in 1944. This remark encourages the minimal or deflationary interpretation of his theory of truth, but see the robust use of 'satisfaction' in Idea 19184.
3. Truth / H. Deflationary Truth / 3. Minimalist Truth
Minimal theories of truth avoid ontological commitment to such things as 'facts' or 'reality' [PG]
     Full Idea: Minimalist theories of truth are those which involve minimum ontological commitment, avoiding references to 'reality' or 'facts' or 'what works', preferring to refer to formal relationships within language.
     From: PG (Db (ideas) [2031])
     A reaction: Personally I am suspicious of minimal theories, which seem to be designed by and for anti-realists. They seem too focused on language, when animals can obviously formulate correct propositions. I'm quite happy with the 'facts', even if that is vague.
4. Formal Logic / B. Propositional Logic PL / 3. Truth Tables
Truth tables give prior conditions for logic, but are outside the system, and not definitions [Tarski]
     Full Idea: Logical sentences are often assigned preliminary conditions under which they are true or false (often given as truth tables). However, these are outside the system of logic, and should not be regarded as definitions of the terms involved.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 15)
     A reaction: Hence, presumably, the connectives are primitives (with no nature or meaning), and the truth tables are axioms for their use? This opinion of Tarski's may have helped shift the preference towards natural deduction introduction and elimination rules.
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Set theory and logic are fairy tales, but still worth studying [Tarski]
     Full Idea: People have asked me, 'How can you, a nominalist, do work in set theory and in logic, which are theories about things you do not believe in?' ...I believe that there is a value even in fairy tales and the study of fairy tales.
     From: Alfred Tarski (talk [1965]), quoted by Feferman / Feferman - Alfred Tarski: life and logic
     A reaction: This is obviously an oversimplification. I don't think for a moment that Tarski literally believed that the study of fairy tales had as much value as the study of logic. Why do we have this particular logic, and not some other?
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
There is no clear boundary between the logical and the non-logical [Tarski]
     Full Idea: No objective grounds are known to me which permit us to draw a sharp boundary between the two groups of terms, the logical and the non-logical.
     From: Alfred Tarski (works [1936]), quoted by Alan Musgrave - Logicism Revisited §3
     A reaction: Musgrave is pointing out that this is bad news if you want to 'reduce' something like arithmetic to logic. 'Logic' is a vague object.
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
A language: primitive terms, then definition rules, then sentences, then axioms, and finally inference rules [Tarski]
     Full Idea: For a language, we must enumerate the primitive terms, and the rules of definition for new terms. Then we must distinguish the sentences, and separate out the axioms from amng them, and finally add rules of inference.
     From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.402)
     A reaction: [compressed] This lays down the standard modern procedure for defining a logical language. Once all of this is in place, we then add a semantics and we are in business. Natural deduction tries to do without the axioms.
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Split out the logical vocabulary, make an assignment to the rest. It's logical if premises and conclusion match [Tarski, by Rumfitt]
     Full Idea: Tarski made a division of logical and non-logical vocabulary. He then defined a model as a non-logical assignment satisfying the corresponding sentential function. Then a conclusion follows logically if every model of the premises models the conclusion.
     From: report of Alfred Tarski (The Concept of Logical Consequence [1936]) by Ian Rumfitt - The Boundary Stones of Thought 3.2
     A reaction: [compressed] This is Tarski's account of logical consequence, which follows on from his account of truth. 'Logical validity' is then 'true in every model'. Rumfitt doubts whether Tarski has given the meaning of 'logical consequence'.
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
Logical consequence is when in any model in which the premises are true, the conclusion is true [Tarski, by Beall/Restall]
     Full Idea: Tarski's 1936 definition of logical consequence is that in any model in which the premises are true, the conclusion is true too (so that no model can make the conclusion false).
     From: report of Alfred Tarski (works [1936]) by JC Beall / G Restall - Logical Consequence 3
     A reaction: So the general idea is that a logical consequence is distinguished by being unstoppable. Sounds good. But then we have monotonic and non-monotonic logics, which (I'm guessing) embody different notions of consequence.
Logical consequence: true premises give true conclusions under all interpretations [Tarski, by Hodges,W]
     Full Idea: Tarski's definition of logical consequence (1936) is that in a fully interpreted formal language an argument is valid iff under any allowed interpretation of its nonlogical symbols, if the premises are true then so is the conclusion.
     From: report of Alfred Tarski (works [1936]) by Wilfrid Hodges - Model Theory 3
     A reaction: The idea that you can only make these claims 'under an interpretation' seems to have had a huge influence on later philosophical thinking.
X follows from sentences K iff every model of K also models X [Tarski]
     Full Idea: The sentence X follows logically from the sentences of the class K if and only if every model of the class K is also a model of the sentence X.
     From: Alfred Tarski (The Concept of Logical Consequence [1936], p.417)
     A reaction: [see Idea 13343 for his account of a 'model'] He is offering to define logical consequence in general, but this definition fits what we now call 'semantic consequence', written |=. This it is standard practice to read |= as 'models'.
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
The truth definition proves semantic contradiction and excluded middle laws (not the logic laws) [Tarski]
     Full Idea: With our definition of truth we can prove the laws of contradiction and excluded middle. These semantic laws should not be identified with the related logical laws, which belong to the sentential calculus, and do not involve 'true' at all.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 12)
     A reaction: Very illuminating. I wish modern thinkers could be so clear about this matter. The logic contains 'P or not-P'. The semantics contains 'P is either true or false'. Critics say Tarski has presupposed 'classical' logic.
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
Identity is invariant under arbitrary permutations, so it seems to be a logical term [Tarski, by McGee]
     Full Idea: Tarski showed that the only binary relations invariant under arbitrary permutations are the universal relation, the empty relation, identity and non-identity, thus giving us a reason to include '=' among the logical terms.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Vann McGee - Logical Consequence 6
     A reaction: Tarski was looking for a criterion to distinguish logical from non-logical terms, since his account of logical validity depended on it. This idea lies behind whether a logic is or is not specified to be 'with identity' (i.e. using '=').
5. Theory of Logic / F. Referring in Logic / 1. Naming / c. Names as referential
A name denotes an object if the object satisfies a particular sentential function [Tarski]
     Full Idea: To say that the name x denotes a given object a is the same as to stipulate that the object a ... satisfies a sentential function of a particular type.
     From: Alfred Tarski (The Concept of Truth for Formalized Languages [1933], p.194)
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
Tarski built a compositional semantics for predicate logic, from dependent satisfactions [Tarski, by McGee]
     Full Idea: Tarski discovered how to give a compositional semantics for predicate calculus, defining truth in terms of satisfaction, and showing how satisfaction for a complicated formula depends on satisfaction of the simple subformulas.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Vann McGee - Logical Consequence 4
     A reaction: The problem was that the subformulas may contain free variables, and thus not be sentences with truth values. 'Satisfaction' can handle this, where 'truth' cannot (I think).
Tarksi invented the first semantics for predicate logic, using this conception of truth [Tarski, by Kirkham]
     Full Idea: Tarski invented a formal semantics for quantified predicate logic, the logic of reasoning about mathematics. The heart of this great accomplishment is his theory of truth. It has been called semantic 'theory' of truth, but Tarski preferred 'conception'.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Richard L. Kirkham - Theories of Truth: a Critical Introduction 5.1
Semantics is the concepts of connections of language to reality, such as denotation, definition and truth [Tarski]
     Full Idea: Semantics is the totality of considerations concerning concepts which express connections between expressions of a language and objects and states of affairs referred to by these expressions. Examples are denotation, satisfaction, definition and truth.
     From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.401)
     A reaction: Interestingly, he notes that it 'is not commonly recognised' that truth is part of semantics. Nowadays truth seems to be the central concept in most semantics.
A language containing its own semantics is inconsistent - but we can use a second language [Tarski]
     Full Idea: People have not been aware that the language about which we speak need by no means coincide with the language in which we speak. ..But the language which contains its own semantics must inevitably be inconsistent.
     From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.402)
     A reaction: It seems that Tarski was driven to propose the metalanguage approach mainly by the Liar Paradox.
5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction
A sentence is satisfied when we can assert the sentence when the variables are assigned [Tarski]
     Full Idea: Here is a partial definition of the concept of satisfaction: John and Peter satisfy the sentential function 'X and Y are brothers' if and only if John and Peter are brothers.
     From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.405)
     A reaction: Satisfaction applies to open sentences and truth to closed sentences (with named objects). He uses the notion of total satisfaction to define truth. The example is a partial definition, not just an illustration.
Satisfaction is the easiest semantical concept to define, and the others will reduce to it [Tarski]
     Full Idea: It has been found useful in defining semantical concepts to deal first with the concept of satisfaction; both because the definition of this concept presents relatively few difficulties, and because the other semantical concepts are easily reduced to it.
     From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.406)
     A reaction: See Idea 13339 for his explanation of satisfaction. We just say that a open sentence is 'acceptable' or 'assertible' (or even 'true') when particular values are assigned to the variables. Then sentence is then 'satisfied'.
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
The object language/ metalanguage distinction is the basis of model theory [Tarski, by Halbach]
     Full Idea: Tarski's distinction between object and metalanguage forms the basis of model theory.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 11
A 'model' is a sequence of objects which satisfies a complete set of sentential functions [Tarski]
     Full Idea: An arbitrary sequence of objects which satisfies every sentential function of the sentences L' will be called a 'model' or realization of the class L of sentences. There can also be a model of a single sentence is this way.
     From: Alfred Tarski (The Concept of Logical Consequence [1936], p.417)
     A reaction: [L' is L with the constants replaced by variables] Tarski is the originator of model theory, which is central to modern logic. The word 'realization' is a helpful indicator of what he has in mind. A model begins to look like a possible world.
5. Theory of Logic / K. Features of Logics / 2. Consistency
Using the definition of truth, we can prove theories consistent within sound logics [Tarski]
     Full Idea: Using the definition of truth we are in a position to carry out the proof of consistency for deductive theories in which only (materially) true sentences are (formally) provable.
     From: Alfred Tarski (The Establishment of Scientific Semantics [1936], p.407)
     A reaction: This is evidently what Tarski saw as the most important first fruit of his new semantic theory of truth.
5. Theory of Logic / L. Paradox / 1. Paradox
Monty Hall Dilemma: do you abandon your preference after Monty eliminates one of the rivals? [PG]
     Full Idea: The Monty Hall Dilemma: Three boxes, one with a big prize; pick one to open. Monty Hall then opens one of the other two, which is empty. You may, if you wish, switch from your box to the other unopened box. Should you?
     From: PG (Db (ideas) [2031])
     A reaction: The other two boxes, as a pair, are more likely contain the prize than your box. Monty Hall has eliminated one of them for you, so you should choose the other one. Your intuition that the two remaining boxes are equal is incorrect!
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
Tarski avoids the Liar Paradox, because truth cannot be asserted within the object language [Tarski, by Fisher]
     Full Idea: In Tarski's account of truth, self-reference (as found in the Liar Paradox) is prevented because the truth predicate for any given object language is never a part of that object language, and so a sentence can never predicate truth of itself.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Jennifer Fisher - On the Philosophy of Logic 03.I
     A reaction: Thus we solve the Liar Paradox by ruling that 'you are not allowed to say that'. Hm. The slightly odd result is that in any conversation about whether p is true, we end up using (logically speaking) two different languages simultaneously. Hm.
The Liar makes us assert a false sentence, so it must be taken seriously [Tarski]
     Full Idea: In my judgement, it would be quite wrong and dangerous from the point of view of scientific progress to depreciate the importance of nhtinomies like the Liar Paradox, and treat them as jokes. The fact is we have been compelled to assert a false sentence.
     From: Alfred Tarski (The Semantic Conception of Truth [1944], 07)
     A reaction: This is the heartfelt cry of the perfectionist, who wants everything under control. It was the dream of the age of Frege to Hilbert, which gradually eroded after Gödel's Incompleteness proof. Short ordinary folk panic about the Liar?
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
Tarski improved Hilbert's geometry axioms, and without set-theory [Tarski, by Feferman/Feferman]
     Full Idea: Tarski found an elegant new axiom system for Euclidean geometry that improved Hilbert's earlier version - and he formulated it without the use of set-theoretical notions.
     From: report of Alfred Tarski (works [1936]) by Feferman / Feferman - Alfred Tarski: life and logic Ch.9
6. Mathematics / C. Sources of Mathematics / 7. Formalism
Tarski's theory of truth shifted the approach away from syntax, to set theory and semantics [Feferman/Feferman on Tarski]
     Full Idea: Tarski's theory of truth has been most influential in eventually creating a shift from the entirely syntactic way of doing things in metamathematics (promoted by Hilbert in the 1920s, in his theory of proofs), towards a set-theoretical, semantic approach.
     From: comment on Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Feferman / Feferman - Alfred Tarski: life and logic Int III
8. Modes of Existence / E. Nominalism / 1. Nominalism / a. Nominalism
I am a deeply convinced nominalist [Tarski]
     Full Idea: I am a nominalist. This is a very deep conviction of mine. ...I am a tortured nominalist.
     From: Alfred Tarski (talk [1965]), quoted by Feferman / Feferman - Alfred Tarski: life and logic Int I
     A reaction: I too am of the nominalist persuasion, but I don't feel justified in such a strong commitment.
10. Modality / B. Possibility / 6. Probability
Everything has a probability, something will happen, and probabilities add up [PG]
     Full Idea: The three Kolgorov axioms of probability: the probability of an event is a non-negative real number; it is certain that one of the 'elementary events' will occur; and the unity of probabilities is the sum of probability of parts ('additivity').
     From: PG (Db (ideas) [2031])
     A reaction: [My attempt to verbalise them; they are normally expressed in terms of set theory]. Got this from a talk handout, and Wikipedia.
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / a. Naďve realism
If reality is just what we perceive, we would have no need for a sixth sense [PG]
     Full Idea: Reality must be more than merely what we perceive, because a sixth sense would enhance our current knowledge, and a seventh, and so on.
     From: PG (Db (ideas) [2031])
12. Knowledge Sources / A. A Priori Knowledge / 5. A Priori Synthetic
If my team is losing 3-1, I have synthetic a priori knowledge that they need two goals for a draw [PG]
     Full Idea: If my football team is losing 3-1, I seem to have synthetic a priori knowledge that they need two goals to achieve a draw
     From: PG (Db (ideas) [2031])
17. Mind and Body / E. Mind as Physical / 7. Anti-Physicalism / b. Multiple realisability
Maybe a mollusc's brain events for pain ARE of the same type (broadly) as a human's [PG]
     Full Idea: To defend type-type identity against the multiple realisability objection, we might say that a molluscs's brain events that register pain ARE of the same type as humans, given that being 'of the same type' is a fairly flexible concept.
     From: PG (Db (ideas) [2031])
     A reaction: But this reduces 'of the same type' to such vagueness that it may become vacuous. You would be left with token-token identity, where the mental event is just identical to some brain event, with its 'type' being irrelevant.
Maybe a frog's brain events for fear are functionally like ours, but not phenomenally [PG]
     Full Idea: To defend type-type identity against the multiple realisability objection, we might (also) say that while a frog's brain events for fear are functionally identical to a human's (it runs away), that doesn't mean they are phenomenally identical.
     From: PG (Db (ideas) [2031])
     A reaction: I take this to be the key reply to the multiple realisability problem. If a frog flees from a loud noise, it is 'frightened' in a functional sense, but that still leaves the question 'What's it like to be a frightened frog?', which may differ from humans.
19. Language / E. Analyticity / 1. Analytic Propositions
Sentences are 'analytical' if every sequence of objects models them [Tarski]
     Full Idea: A class of sentences can be called 'analytical' if every sequence of objects is a model of it.
     From: Alfred Tarski (The Concept of Logical Consequence [1936], p.418)
     A reaction: See Idea 13344 and Idea 13343 for the context of this assertion.
21. Aesthetics / A. Aesthetic Experience / 3. Taste
Taste is the capacity to judge an object or representation which is thought to be beautiful [Tarski, by Schellekens]
     Full Idea: Taste is the faculty for judging an object or a kind of representation through a satisfaction or a dissatisfaction, ...where the object of such a satisfaction is called beautiful.
     From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Elizabeth Schellekens - Immanuel Kant (aesthetics) 1
     A reaction: We usually avoid the word 'faculty' nowadays, because it implies a specific mechanism, but 'capacity' will do. Kant is said to focus specifically on beauty, whereas modern aestheticians have a broader view of the type of subject matter.
23. Ethics / E. Utilitarianism / 4. Unfairness
Utilitarianism seems to justify the discreet murder of unhappy people [PG]
     Full Idea: If I discreetly murdered a gloomy and solitary tramp who was upsetting people in my village, if is hard to see how utilitarianism could demonstrate that I had done something wrong.
     From: PG (Db (ideas) [2031])
27. Natural Reality / G. Biology / 2. Life
Life is Movement, Respiration, Sensation, Nutrition, Excretion, Reproduction, Growth (MRS NERG) [PG]
     Full Idea: The biologists' acronym for the necessary conditions of life is MRS NERG: that is, Movement, Respiration, Sensation, Nutrition, Excretion, Reproduction, Growth.
     From: PG (Db (ideas) [2031])
     A reaction: How strictly necessary are each of these is a point for discussion. A notorious problem case is fire, which (at a stretch) may pass all seven tests.
28. God / A. Divine Nature / 4. Divine Contradictions
An omniscient being couldn't know it was omniscient, as that requires information from beyond its scope of knowledge [PG]
     Full Idea: God seems to be in the paradoxical situation that He may be omniscient, but can never know that He is, because that involves knowing that there is nothing outside his scope of knowledge (e.g. another God)
     From: PG (Db (ideas) [2031])
How could God know there wasn't an unknown force controlling his 'free' will? [PG]
     Full Idea: How could God be certain that he has free will (if He has), if He couldn't be sure that there wasn't an unknown force controlling his will?
     From: PG (Db (ideas) [2031])