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All the ideas for 'fragments/reports', 'On the Foundations of Logic and Arithmetic' and 'Tarski's Theory of Truth'

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33 ideas

3. Truth / A. Truth Problems / 4. Uses of Truth
The notion of truth is to help us make use of the utterances of others [Field,H]
     Full Idea: I suspect that the original purpose of the notion of truth was to aid us in utilizing the utterances of others in drawing conclusions about the world,...so we must attend to its social role, and that being in a position to assert something is what counts.
     From: Hartry Field (Tarski's Theory of Truth [1972], §5)
     A reaction: [Last bit compressed] This sounds excellent. Deflationary and redundancy views are based on a highly individualistic view of utterances and truth, but we need to be much more contextual and pragmatic if we are to get the right story.
3. Truth / A. Truth Problems / 9. Rejecting Truth
In the early 1930s many philosophers thought truth was not scientific [Field,H]
     Full Idea: In the early 1930s many philosophers believed that the notion of truth could not be incorporated into a scientific conception of the world.
     From: Hartry Field (Tarski's Theory of Truth [1972], §3)
     A reaction: This leads on to an account of why Tarski's formal version was so important, and Field emphasises Tarski's physicalist metaphysic.
3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
Tarski reduced truth to reference or denotation [Field,H, by Hart,WD]
     Full Idea: Tarski can be viewed as having reduced truth to reference or denotation.
     From: report of Hartry Field (Tarski's Theory of Truth [1972]) by William D. Hart - The Evolution of Logic 4
Tarski really explained truth in terms of denoting, predicating and satisfied functions [Field,H]
     Full Idea: A proper account of Tarski's truth definition explains truth in terms of three other semantic notions: what it is for a name to denote something, and for a predicate to apply to something, and for a function symbol to be fulfilled by a pair of things.
     From: Hartry Field (Tarski's Theory of Truth [1972])
     A reaction: This is Field's 'T1' version, which is meant to spell out what was really going on in Tarski's account.
3. Truth / F. Semantic Truth / 1. Tarski's Truth / b. Satisfaction and truth
Tarski just reduced truth to some other undefined semantic notions [Field,H]
     Full Idea: It is normally claimed that Tarski defined truth using no undefined semantic terms, but I argue that he reduced the notion of truth to certain other semantic notions, but did not in any way explicate these other notions.
     From: Hartry Field (Tarski's Theory of Truth [1972], §0)
5. Theory of Logic / I. Semantics of Logic / 2. Formal Truth
Tarski gives us the account of truth needed to build a group of true sentences in a model [Field,H]
     Full Idea: Model theory must choose the denotations of the primitives so that all of a group of sentences come out true, so we need a theory of how the truth value of a sentence depends on the denotation of its primitive nonlogical parts, which Tarski gives us.
     From: Hartry Field (Tarski's Theory of Truth [1972], §1)
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
Model theory is unusual in restricting the range of the quantifiers [Field,H]
     Full Idea: In model theory we are interested in allowing a slightly unusual semantics for quantifiers: we are willing to allow that the quantifier not range over everything.
     From: Hartry Field (Tarski's Theory of Truth [1972], n 5)
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / c. Against mathematical empiricism
The existence of an arbitrarily large number refutes the idea that numbers come from experience [Hilbert]
     Full Idea: The standpoint of pure experience seems to me to be refuted by the objection that the existence, possible or actual, of an arbitrarily large number can never be derived through experience, that is, through experiment.
     From: David Hilbert (On the Foundations of Logic and Arithmetic [1904], p.130)
     A reaction: Alternatively, empiricism refutes infinite numbers! No modern mathematician will accept that, but you wonder in what sense the proposed entities qualify as 'numbers'.
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Logic already contains some arithmetic, so the two must be developed together [Hilbert]
     Full Idea: In the traditional exposition of the laws of logic certain fundamental arithmetic notions are already used, for example in the notion of set, and to some extent also of number. Thus we turn in a circle, and a partly simultaneous development is required.
     From: David Hilbert (On the Foundations of Logic and Arithmetic [1904], p.131)
     A reaction: If the Axiom of Infinity is meant, it may be possible to purge the arithmetic from the logic. Then the challenge to derive arithmetic from it becomes rather tougher.
7. Existence / A. Nature of Existence / 5. Reason for Existence
Nothing could come out of nothing, and existence could never completely cease [Empedocles]
     Full Idea: From what in no wise exists, it is impossible for anything to come into being; for Being to perish completely is incapable of fulfilment and unthinkable.
     From: Empedocles (fragments/reports [c.453 BCE], B012), quoted by Anon (Lyc) - On Melissus 975b1-4
     A reaction: The first statement of a conservation law. Modern physics is wonderful, but hasn't offered a flicker of an answer to this puzzle. Quantum fluctuations are a mode of Being.
7. Existence / B. Change in Existence / 1. Nature of Change
Empedocles says things are at rest, unless love unites them, or hatred splits them [Empedocles, by Aristotle]
     Full Idea: Empedocles claims that things are alternately changing and at rest - that they are changing whenever love is creating a unity out of plurality, or hatred is creating plurality out of unity, and they are at rest in the times in between.
     From: report of Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Physics 250b26
     A reaction: I suppose one must say that this an example of Ruskin's 'pathetic fallacy' - reading human emotions into the cosmos. Being constructive little creatures, we think goodness leads to construction. I'm afraid Empedocles is just wrong.
9. Objects / A. Existence of Objects / 6. Nihilism about Objects
There is no coming-to-be of anything, but only mixing and separating [Empedocles, by Aristotle]
     Full Idea: Empedocles says there is no coming-to-be of anything, but only a mingling and a divorce of what has been mingled.
     From: report of Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 314b08
     A reaction: Aristotle comments that this prevents Empedocleans from distinguishing between superficial alteration and fundamental change of identity. Presumably, though, that wouldn't bother them.
9. Objects / E. Objects over Time / 10. Beginning of an Object
Substance is not created or destroyed in mortals, but there is only mixing and exchange [Empedocles]
     Full Idea: There is no creation of substance in any one of mortal existence, nor any end in execrable death, but only mixing and exchange of what has been mixed.
     From: Empedocles (fragments/reports [c.453 BCE], B008), quoted by Plutarch - 74: Reply to Colotes 1111f
     A reaction: also Aristotle 314b08
13. Knowledge Criteria / E. Relativism / 3. Subjectivism
One vision is produced by both eyes [Empedocles]
     Full Idea: One vision is produced by both eyes
     From: Empedocles (fragments/reports [c.453 BCE], B088), quoted by Strabo - works 8.364.3
17. Mind and Body / A. Mind-Body Dualism / 3. Panpsychism
Wisdom and thought are shared by all things [Empedocles]
     Full Idea: Wisdom and power of thought, know thou, are shared in by all things.
     From: Empedocles (fragments/reports [c.453 BCE]), quoted by Sextus Empiricus - Against the Logicians (two books) II.286
     A reaction: Sextus quotes this, saying that it is 'still more paradoxical', and that it explicitly includes plants. This may mean that Empedocles was not including inanimate matter.
17. Mind and Body / E. Mind as Physical / 2. Reduction of Mind
'Valence' and 'gene' had to be reduced to show their compatibility with physicalism [Field,H]
     Full Idea: 'Valence' and 'gene' were perfectly clear long before anyone succeeded in reducing them, but it was their reducibility and not their clarity before reduction that showed them to be compatible with physicalism.
     From: Hartry Field (Tarski's Theory of Truth [1972], §5)
18. Thought / A. Modes of Thought / 1. Thought
For Empedocles thinking is almost identical to perception [Empedocles, by Theophrastus]
     Full Idea: Empedocles assumes that thinking is either identical to or very similar to sense-perception.
     From: report of Empedocles (fragments/reports [c.453 BCE], A86) by Theophrastus - On the Senses 9
     A reaction: Not to be sniffed at. We can, of course, control our thinking (though we can't control the controller) and we contemplate abstractions, but that might be seen as a sort of perception. Vision is not as visual as we think.
19. Language / B. Reference / 3. Direct Reference / b. Causal reference
Field says reference is a causal physical relation between mental states and objects [Field,H, by Putnam]
     Full Idea: In Field's view reference is a 'physicalistic relation', i.e. a complex causal relation between words or mental representations and objects or sets of objects; it is up to physical science to discover what that physicalistic relation is.
     From: report of Hartry Field (Tarski's Theory of Truth [1972]) by Hilary Putnam - Reason, Truth and History Ch.2
     A reaction: I wouldn't hold your breath while the scientists do their job. If physicalism is right then Field is right, but physics seems no more appropriate for giving a theory of reference than it does for giving a theory of music.
22. Metaethics / B. Value / 2. Values / j. Evil
Empedocles said good and evil were the basic principles [Empedocles, by Aristotle]
     Full Idea: Empedocles was the first to give evil and good as principles.
     From: report of Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Metaphysics 985a
     A reaction: Once you start to think that good and evil will only matter if they have causal powers, it is an easy step to the idea of a benevolent god, and a satanic anti-god. Otherwise the 'principles' could be ignored.
26. Natural Theory / A. Speculations on Nature / 1. Nature
'Nature' is just a word invented by people [Empedocles]
     Full Idea: Nature is but a word of human framing.
     From: Empedocles (fragments/reports [c.453 BCE], B008), quoted by Aristotle - Metaphysics 1015a
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / e. The One
The principle of 'Friendship' in Empedocles is the One, and is bodiless [Empedocles, by Plotinus]
     Full Idea: In Empedocles we have a dividing principle, 'Strife', set against 'Friendship' - which is the One and is to him bodiless, while the elements represent matter.
     From: report of Empedocles (fragments/reports [c.453 BCE]) by Plotinus - The Enneads 5.1.09
     A reaction: The first time I've seen the principle of Love in Empedocles identified with the One of Parmenides. Plotinus is a trustworthy reporter, I think, because he was well read, and had access to lost texts.
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / f. Ancient elements
Empedocles says bone is water, fire and earth in ratio 2:4:2 [Empedocles, by Inwood]
     Full Idea: Empedocles used numerical ratios to explain different kinds of matter; for example, bone is two parts water, four parts fire, two parts earth; and blood is an equal blend of all four elements.
     From: report of Empedocles (fragments/reports [c.453 BCE]) by Brad Inwood - Empedocles
     A reaction: Why isn't the ration 1:2:1? This presumably shows the influence of Pythagoras (who had also been based in Italy, like Empedocles), as well as that of the earlier naturalistic philosophers. It was a very good theory, though wrong.
Fire, Water, Air and Earth are elements, being simple as well as homoeomerous [Empedocles, by Aristotle]
     Full Idea: Empedocles says that Fire, Water, Air and Earth are four elements, and are thus 'simple' rather than flesh, bone and bodies which, like these, are 'homoeomeries'.
     From: report of Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 314a26
     A reaction: The translation is not quite clear. I take it that flesh and bone may look simple, because they are homoeomerous, but they are not really - but what is his evidence for that? Compare Idea 13208.
All change is unity through love or division through hate [Empedocles]
     Full Idea: These elements never cease their continuous exchange, sometimes uniting under the influence of Love, so that all become One, at other times again moving apart through the hostile force of Hate.
     From: Empedocles (fragments/reports [c.453 BCE], B017), quoted by Simplicius - On Aristotle's 'Physics' 158.1-
The elements combine in coming-to-be, but how do the elements themselves come-to-be? [Aristotle on Empedocles]
     Full Idea: Empedocles says it is evident that all the other bodies down to the 'elements' have their coming-to-be and their passing-away: but it is not clear how the 'elements' themselves, severally in their aggregated masses, come-to-be and pass-away.
     From: comment on Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 325b20
     A reaction: Presumably the elements are like axioms - and are just given. How do electrons and quarks come-to-be?
Love and Strife only explain movement if their effects are distinctive [Aristotle on Empedocles]
     Full Idea: It is not an adequate explanation to say that 'Love and Strife set things moving', unless the very nature of Love is a movement of this kind and the very nature of Strife a movement of that kind.
     From: comment on Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 333b23
     A reaction: I take this to be of interest for showing Aristotle's quest for explanations, and his unwillingness to be fobbed off with anything superficial. I take a task of philosophy to be to push explanations further than others wish to go.
If the one Being ever diminishes it would no longer exist, and what could ever increase it? [Empedocles]
     Full Idea: Besides these elements, nothing else comes into being, nor does anything cease. For if they had been perishing continuously, they would Be no more; and what could increase the Whole? And whence could it have come?
     From: Empedocles (fragments/reports [c.453 BCE], B017), quoted by Simplicius - On Aristotle's 'Physics' 158.1-
Empedocles said that there are four material elements, and two further creative elements [Empedocles, by Aristotle]
     Full Idea: Empedocles holds that the corporeal elements are four, but that all the elements, including those which create motion, are six in number.
     From: report of Empedocles (fragments/reports [c.453 BCE]) by Aristotle - Coming-to-be and Passing-away (Gen/Corr) 314a16
27. Natural Reality / G. Biology / 3. Evolution
Maybe bodies are designed by accident, and the creatures that don't work are destroyed [Empedocles, by Aristotle]
     Full Idea: Is it just an accident that teeth and other parts of the body seem to have some purpose, and creatures survive because they happen to be put together in a useful way? Everything else has been destroyed, as Empedocles says of his 'cow with human head'.
     From: report of Empedocles (fragments/reports [c.453 BCE], 61) by Aristotle - Physics 198b29
     A reaction: Good grief! Has no one ever noticed that Empedocles proposed the theory of evolution? It isn't quite natural selection, because we aren't told what does the 'destroying', but it is a little flash of genius that was quietly forgotten.
28. God / A. Divine Nature / 2. Divine Nature
God is a pure, solitary, and eternal sphere [Empedocles]
     Full Idea: God is equal in all directions to himself and altogether eternal, a rounded Sphere enjoying a circular solitude.
     From: Empedocles (fragments/reports [c.453 BCE], B028), quoted by John Stobaeus - Anthology 1.15.2
God is pure mind permeating the universe [Empedocles]
     Full Idea: God is mind, holy and ineffable, and only mind, which darts through the whole cosmos with its swift thought.
     From: Empedocles (fragments/reports [c.453 BCE], B134), quoted by Ammonius - On 'De Interpretatione' 4.5.249.6
28. God / A. Divine Nature / 4. Divine Contradictions
In Empedocles' theory God is ignorant because, unlike humans, he doesn't know one of the elements (strife) [Aristotle on Empedocles]
     Full Idea: It is a consequence of Empedocles' view that God is the most unintelligent thing, for he alone is ignorant of one of the elements, namely strife, whereas mortal creatures are familiar with them all.
     From: comment on Empedocles (fragments/reports [c.453 BCE]) by Aristotle - De Anima 410b08
29. Religion / A. Polytheistic Religion / 2. Greek Polytheism
It is wretched not to want to think clearly about the gods [Empedocles]
     Full Idea: Wretched is he who cares not for clear thinking about the gods.
     From: Empedocles (fragments/reports [c.453 BCE], B132), quoted by Clement - Miscellanies 5.140.5.1