Combining Philosophers

All the ideas for Lucretius, Heraclitus and Alfred Tarski

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157 ideas

1. Philosophy / A. Wisdom / 2. Wise People
Men who love wisdom must be inquirers into very many things indeed [Heraclitus]
1. Philosophy / D. Nature of Philosophy / 2. Invocation to Philosophy
Everyone has the potential for self-knowledge and sound thinking [Heraclitus]
1. Philosophy / D. Nature of Philosophy / 7. Despair over Philosophy
Reason is eternal, but men are foolish [Heraclitus]
1. Philosophy / E. Nature of Metaphysics / 5. Metaphysics beyond Science
Some say metaphysics is a highly generalised empirical study of objects [Tarski]
1. Philosophy / F. Analytic Philosophy / 1. Nature of Analysis
Disputes that fail to use precise scientific terminology are all meaningless [Tarski]
2. Reason / A. Nature of Reason / 2. Logos
Logos is common to all, but most people live as if they have a private understanding [Heraclitus]
2. Reason / B. Laws of Thought / 5. Opposites
A thing can have opposing tensions but be in harmony, like a lyre [Heraclitus]
Beautiful harmony comes from things that are in opposition to one another [Heraclitus]
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]
3. Truth / A. Truth Problems / 1. Truth
The concept of truth was originated by the senses [Lucretius]
3. Truth / A. Truth Problems / 2. Defining Truth
In everyday language, truth seems indefinable, inconsistent, and illogical [Tarski]
Tarski proved that truth cannot be defined from within a given theory [Tarski, by Halbach]
Tarski proved that any reasonably expressive language suffers from the liar paradox [Tarski, by Horsten]
'True sentence' has no use consistent with logic and ordinary language, so definition seems hopeless [Tarski]
Definitions of truth should not introduce a new version of the concept, but capture the old one [Tarski]
A definition of truth should be materially adequate and formally correct [Tarski]
A rigorous definition of truth is only possible in an exactly specified language [Tarski]
We may eventually need to split the word 'true' into several less ambiguous terms [Tarski]
3. Truth / C. Correspondence Truth / 3. Correspondence Truth critique
Tarski's Theorem renders any precise version of correspondence impossible [Tarski, by Halbach]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
Scheme (T) is not a definition of truth [Tarski]
Tarski gave up on the essence of truth, and asked how truth is used, or how it functions [Tarski, by Horsten]
Tarski did not just aim at a definition; he also offered an adequacy criterion for any truth definition [Tarski, by Halbach]
Tarski enumerates cases of truth, so it can't be applied to new words or languages [Davidson on Tarski]
Tarski define truths by giving the extension of the predicate, rather than the meaning [Davidson on Tarski]
Tarski made truth relative, by only defining truth within some given artificial language [Tarski, by O'Grady]
Tarski has to avoid stating how truths relate to states of affairs [Kirkham on Tarski]
Tarskian semantics says that a sentence is true iff it is satisfied by every sequence [Tarski, by Hossack]
'"It is snowing" is true if and only if it is snowing' is a partial definition of the concept of truth [Tarski]
It is convenient to attach 'true' to sentences, and hence the language must be specified [Tarski]
In the classical concept of truth, 'snow is white' is true if snow is white [Tarski]
Use 'true' so that all T-sentences can be asserted, and the definition will then be 'adequate' [Tarski]
Each interpreted T-sentence is a partial definition of truth; the whole definition is their conjunction [Tarski]
We don't give conditions for asserting 'snow is white'; just that assertion implies 'snow is white' is true [Tarski]
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]
Tarski uses sentential functions; truly assigning the objects to variables is what satisfies them [Tarski, by Rumfitt]
We can define the truth predicate using 'true of' (satisfaction) for variables and some objects [Tarski, by Horsten]
For physicalism, reduce truth to satisfaction, then define satisfaction as physical-plus-logic [Tarski, by Kirkham]
Insight: don't use truth, use a property which can be compositional in complex quantified sentence [Tarski, by Kirkham]
Tarski gave axioms for satisfaction, then derived its explicit definition, which led to defining truth [Tarski, by Davidson]
The best truth definition involves other semantic notions, like satisfaction (relating terms and objects) [Tarski]
Specify satisfaction for simple sentences, then compounds; true sentences are satisfied by all objects [Tarski]
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]
The metalanguage must contain the object language, logic, and defined semantics [Tarski]
3. Truth / F. Semantic Truth / 2. Semantic Truth
Tarski defined truth for particular languages, but didn't define it across languages [Davidson on Tarski]
Tarski didn't capture the notion of an adequate truth definition, as Convention T won't prove non-contradiction [Halbach on Tarski]
Tarski says that his semantic theory of truth is completely neutral about all metaphysics [Tarski, by Haack]
Physicalists should explain reference nonsemantically, rather than getting rid of it [Tarski, by Field,H]
A physicalist account must add primitive reference to Tarski's theory [Field,H on Tarski]
If listing equivalences is a reduction of truth, witchcraft is just a list of witch-victim pairs [Field,H on Tarski]
Tarski made truth respectable, by proving that it could be defined [Tarski, by Halbach]
Tarski had a theory of truth, and a theory of theories of truth [Tarski, by Read]
Tarski's 'truth' is a precise relation between the language and its semantics [Tarski, by Walicki]
Tarskian truth neglects the atomic sentences [Mulligan/Simons/Smith on Tarski]
3. Truth / G. Axiomatic Truth / 1. Axiomatic Truth
Tarski defined truth, but an axiomatisation can be extracted from his inductive clauses [Tarski, by Halbach]
Tarski's had the first axiomatic theory of truth that was minimally adequate [Tarski, by Horsten]
Tarski thought axiomatic truth was too contingent, and in danger of inconsistencies [Tarski, by Davidson]
We need an undefined term 'true' in the meta-language, specified by axioms [Tarski]
3. Truth / H. Deflationary Truth / 1. Redundant Truth
Truth can't be eliminated from universal claims, or from particular unspecified claims [Tarski]
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
Semantics is a very modest discipline which solves no real problems [Tarski]
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]
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Set theory and logic are fairy tales, but still worth studying [Tarski]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
There is no clear boundary between the logical and the non-logical [Tarski]
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]
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]
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]
Logical consequence: true premises give true conclusions under all interpretations [Tarski, by Hodges,W]
X follows from sentences K iff every model of K also models X [Tarski]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
If everything is and isn't then everything is true, and a midway between true and false makes everything false [Aristotle on Heraclitus]
The truth definition proves semantic contradiction and excluded middle laws (not the logic laws) [Tarski]
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]
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]
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]
Tarksi invented the first semantics for predicate logic, using this conception of truth [Tarski, by Kirkham]
Semantics is the concepts of connections of language to reality, such as denotation, definition and truth [Tarski]
A language containing its own semantics is inconsistent - but we can use a second language [Tarski]
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]
Satisfaction is the easiest semantical concept to define, and the others will reduce to it [Tarski]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
A 'model' is a sequence of objects which satisfies a complete set of sentential functions [Tarski]
The object language/ metalanguage distinction is the basis of model theory [Tarski, by Halbach]
5. Theory of Logic / K. Features of Logics / 2. Consistency
Using the definition of truth, we can prove theories consistent within sound logics [Tarski]
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]
The Liar makes us assert a false sentence, so it must be taken seriously [Tarski]
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
Tarski improved Hilbert's geometry axioms, and without set-theory [Tarski, by Feferman/Feferman]
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]
8. Modes of Existence / C. Powers and Dispositions / 4. Powers as Essence
The hidden harmony is stronger than the visible [Heraclitus]
8. Modes of Existence / E. Nominalism / 1. Nominalism / a. Nominalism
I am a deeply convinced nominalist [Tarski]
9. Objects / A. Existence of Objects / 6. Nihilism about Objects
Everything gives way, and nothing stands fast [Heraclitus]
9. Objects / B. Unity of Objects / 3. Unity Problems / e. Vague objects
A mixed drink separates if it is not stirred [Heraclitus]
9. Objects / E. Objects over Time / 8. Continuity of Rivers
You can bathe in the same river twice, but not in the same river stage [Quine on Heraclitus]
It is not possible to step twice into the same river [Heraclitus]
9. Objects / E. Objects over Time / 13. No Identity over Time
If flux is continuous, then lack of change can't be a property, so everything changes in every possible way [Plato on Heraclitus]
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Senses are no use if the soul is corrupt [Heraclitus]
12. Knowledge Sources / D. Empiricism / 4. Pro-Empiricism
If the senses are deceptive, reason, which rests on them, is even worse [Lucretius]
When we sleep, reason closes down as the senses do [Heraclitus, by Sext.Empiricus]
The senses are much the best way to distinguish true from false [Lucretius]
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / c. Empirical foundations
The only possible standard for settling doubts is the foundation of the senses [Lucretius]
13. Knowledge Criteria / D. Scepticism / 3. Illusion Scepticism
Most supposed delusions of the senses are really misinterpretations by the mind [Lucretius]
13. Knowledge Criteria / E. Relativism / 1. Relativism
Sea water is life-giving for fish, but not for people [Heraclitus]
Donkeys prefer chaff to gold [Heraclitus]
13. Knowledge Criteria / E. Relativism / 3. Subjectivism
Health, feeding and rest are only made good by disease, hunger and weariness [Heraclitus]
14. Science / C. Induction / 1. Induction
Even simple facts are hard to believe at first hearing [Lucretius]
15. Nature of Minds / A. Nature of Mind / 1. Mind / d. Location of mind
The mind is in the middle of the breast, because there we experience fear and joy [Lucretius]
The mind is a part of a man, just like a hand or an eye [Lucretius]
15. Nature of Minds / A. Nature of Mind / 5. Unity of Mind
The separate elements and capacities of a mind cannot be distinguished [Lucretius]
16. Persons / F. Free Will / 2. Sources of Free Will
The actions of the mind are not determinate and passive, because atoms can swerve [Lucretius]
17. Mind and Body / A. Mind-Body Dualism / 2. Interactionism
Only bodies can touch one another [Lucretius]
17. Mind and Body / A. Mind-Body Dualism / 3. Panpsychism
The earth is and always has been an insentient being [Lucretius]
Particles may have sensation, but eggs turning into chicks suggests otherwise [Lucretius]
17. Mind and Body / E. Mind as Physical / 1. Physical Mind
The mind moves limbs, wakes the body up, changes facial expressions, which involve touch [Lucretius]
Lions, foxes and deer have distinct characters because their minds share in their bodies [Lucretius]
17. Mind and Body / E. Mind as Physical / 2. Reduction of Mind
You needn't be made of laughing particles to laugh, so why not sensation from senseless seeds? [Lucretius]
19. Language / E. Analyticity / 1. Analytic Propositions
Sentences are 'analytical' if every sequence of objects models them [Tarski]
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]
21. Aesthetics / C. Artistic Issues / 5. Objectivism in Art
One man's meat is another man's poison [Lucretius]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / e. Ethical cognitivism
To God (though not to humans) all things are beautiful and good and just [Heraclitus]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / h. Against ethics
Good and evil are the same thing [Heraclitus, by Aristotle]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
Our bodies weren't created to be used; on the contrary, their creation makes a use possible [Lucretius]
22. Metaethics / B. Value / 1. Nature of Value / e. Means and ends
If one does not hope, one will not find the unhoped-for, since nothing leads to it [Heraclitus]
22. Metaethics / B. Value / 2. Values / e. Death
The dead are no different from those who were never born [Lucretius]
22. Metaethics / C. The Good / 1. Goodness / f. Good as pleasure
If happiness is bodily pleasure, then oxen are happy when they have vetch to eat [Heraclitus]
22. Metaethics / C. The Good / 3. Pleasure / e. Role of pleasure
Nature only wants two things: freedom from pain, and pleasure [Lucretius]
22. Metaethics / C. The Good / 3. Pleasure / f. Dangers of pleasure
It is hard to fight against emotion, but harder still to fight against pleasure [Heraclitus]
23. Ethics / C. Virtue Theory / 2. Elements of Virtue Theory / e. Character
For man character is destiny [Heraclitus]
25. Social Practice / D. Justice / 2. The Law / b. Rule of law
The people should fight for the law as if for their city-wall [Heraclitus]
26. Natural Theory / A. Speculations on Nature / 1. Nature
Nature runs the universe by herself without the aid of gods [Lucretius]
26. Natural Theory / A. Speculations on Nature / 5. Infinite in Nature
There can be no centre in infinity [Lucretius]
The universe must be limitless, since there could be nothing outside to limit it [Lucretius]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / c. Ultimate substances
Heraclitus said sometimes everything becomes fire [Heraclitus, by Aristotle]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / e. The One
Reason tells us that all things are one [Heraclitus]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / f. Ancient elements
The sayings of Heraclitus are still correct, if we replace 'fire' with 'energy' [Heraclitus, by Heisenberg]
Heraclitus says that at some time everything becomes fire [Heraclitus, by Aristotle]
Heraclitus said fire could be transformed to create the other lower elements [Heraclitus, by Diog. Laertius]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / g. Atomism
Everything is created and fed by nature from atoms, and they return to atoms in death [Lucretius]
If an object is infinitely subdivisible, it will be the same as the whole universe [Lucretius]
In downward motion, atoms occasionally swerve slightly for no reason [Lucretius]
26. Natural Theory / B. Natural Kinds / 4. Source of Kinds
Logos is the source of everything, and my theories separate and explain each nature [Heraclitus]
26. Natural Theory / D. Laws of Nature / 7. Strictness of Laws
Nothing can break the binding laws of eternity [Lucretius]
27. Natural Reality / A. Classical Physics / 1. Mechanics / a. Explaining movement
Atoms move themselves [Lucretius]
All things are in a state of motion [Heraclitus, by Aristotle]
If there were no space there could be no movement, or even creation [Lucretius]
27. Natural Reality / A. Classical Physics / 2. Thermodynamics / d. Entropy
It is quicker to break things up than to assemble them [Lucretius]
27. Natural Reality / D. Time / 2. Passage of Time / a. Experience of time
We can only sense time by means of movement, or its absence [Lucretius]
27. Natural Reality / E. Cosmology / 1. Cosmology
This earth is very unlikely to be the only one created [Lucretius]
27. Natural Reality / E. Cosmology / 2. Eternal Universe
The cosmos is eternal not created, and is an ever-living and changing fire [Heraclitus]
Nothing can be created by divine power out of nothing [Lucretius]
28. God / B. Proving God / 3. Proofs of Evidence / a. Cosmological Proof
If matter wasn't everlasting, everything would have disappeared by now [Lucretius]
28. God / B. Proving God / 3. Proofs of Evidence / b. Teleological Proof
Heraclitus says intelligence draws on divine reason [Heraclitus, by Sext.Empiricus]
28. God / B. Proving God / 3. Proofs of Evidence / c. Teleological Proof critique
The universe can't have been created by gods, because it is too imperfect [Lucretius]
28. God / C. Attitudes to God / 3. Deism
Gods are tranquil and aloof, and have no need of or interest in us [Lucretius]
28. God / C. Attitudes to God / 5. Atheism
Why does Jupiter never hurl lightning from a blue sky? [Lucretius]
29. Religion / A. Polytheistic Religion / 2. Greek Polytheism
Purifying yourself with blood is as crazy as using mud to wash off mud [Heraclitus]
29. Religion / D. Religious Issues / 1. Religious Commitment / a. Religious Belief
In their ignorance people pray to statues, which is like talking to a house [Heraclitus]
29. Religion / D. Religious Issues / 2. Immortality / a. Immortality
Spirit is mortal [Lucretius]
For a separated spirit to remain sentient it would need sense organs attached to it [Lucretius]
An immortal mind couldn't work harmoniously with a mortal body [Lucretius]
29. Religion / D. Religious Issues / 2. Immortality / b. Soul
The mind is very small smooth particles, which evaporate at death [Lucretius]
If spirit is immortal and enters us at birth, why don't we remember a previous existence? [Lucretius]