theories of truth. truth to say of what is that it is not, or of what is not that it is, is falsity....

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Truth and Action True beliefs lead to successful actions.

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Theories of Truth Truth To say of what is that it is not, or of what is not that it is, is falsity. To say of what is that it is, or of what is not that it is not, is truth. Truth and Action True beliefs lead to successful actions. Truth and Action Suppose: You desire to hang out with your friends for another hour. You desire to deposit your paycheck in the bank. You prefer to deposit your check to hanging out with your friends. You believe the bank closes at 6pm. You believe that if you hang out with your friends for another hour, you can still deposit your check. Plan: hang out, then go to the bank. Truth and Action True belief case: You get to hang out and deposit your check. False belief case: Your greatest desire (deposit check) is unsatisfied. The Aim of Belief One view of what belief is, is that belief is the mental state that aims at truth. Knowledge and Truth A mental state is factive if you can only be in that state when the content of that state is true. Knowledge is factive: If you know that p, then p must be true. Grices Maxims Quality: Try to make your contribution one that is true. Quantity: Make your contribution as informative as is required (for the current purposes of the exchange); Do not make your contribution more informative than is required. Grices Maxims Relation: Be relevant. Manner: Be perspicuous. Flouting The form of a flouting inference is something like this: The speaker is openly failing to fulfill such-and-such maxim, though I have strong reason to think the speaker wants the purpose of the conversation to succeed. The only good reason to be uncooperative, given that, would be if q. So the speaker must want me to believe q. Flouting Quality One typically flouts the maxims of quality when one engages in irony, metaphor, understatement, and hyperbole. For example: The speaker said Dick Cheney is a monster; but he cant really believe that Cheney is a monster, because monsters dont exist; he must really mean that Cheney is a terrible person. Why We Are So Clever [A] creature that knows what would make its thoughts true and what would cause it to have them, would be in a highly advantageous epistemic position: Why We Are So Clever It would be able, with premeditation, to cause itself to have true thoughts. In particular, to construct, with malice aforethought, situations in which it will be caused to have the thought that P if and only if the thought that P is true. Why We Are So Clever I think it's likely that we are the only creatures that can think about the contents of our thoughts. Background Criteria vs. Definitions A definition of true gives the meaning of the word true. A criterion for truth gives us a means of telling whether something is true. Some theories of truth are better thought of as giving criteria rather than giving truth-definitions. The Bearers of Truth What sorts of things can be true? Sentence types? Sentence tokens? (utterances) Propositions? Types vs. Tokens Worries about Propositions 1. General issues with abstracta 2. A new kind of going together (unity of the proposition) The Correspondence Theory A correspondence theory of truth views sentences/ propositions that are true as ones that correspond with the facts. Truth the goddess is often depicted holding a mirror: truth mirrors the way the world is. Logical Atomism For (early) Wittgenstein and (atomism-period) Russell, the world was composed of objects, properties, and relations going together. The Facts For example, one fact might be an object, Michael, another object, this particular hat, and the relation of wearing. These objects and relation go together to make a fact. Correspondence Truth then is a correlation between sentences/ propositions and the facts that make them true. Michael is wearing a hat Grass is green Goats wear glasses The Facts Problem: which objects and properties going together constituted the fact that Michael is not wearing a blue shirt? We need this fact to correspond to the sentence Michael is not wearing a blue shirt. Compositional Analysis Maybe the correspondence theory should be applied to the atomic sentences, and more complex sentences have their truth-conditions determined by the truth-conditions of their atomic parts: NOT: P is true iff P is not true (does not correspond with the facts). The Facts Michael is wearing a blue shirt. So: Michael is not wearing a blue shirt is true. Does not correspond The Coherence Theory Neuraths Raft What Is Coherence? Cant be satisfiability! Not mere consistency Comprehensiveness Truth-likeness Criterion or definition? The Pragmatist Theory William James American philosopher/ psychologist Charles Sanders Peirce American philosopher/ logician/ mathematician/ chemist Along with Frege, independently discovered modern logic John Dewey American philosopher/ psychologist/ education reformer Advocate of democracy and education Pragmatism There can be no difference that makes no difference. Peirces Pragmatism Correct definition of truth: correspondence with reality. Way to tell whether something is true: use science. Criterion for truth: what we believe at the end of inquiry. Primitivism, Redundancy, Delfationism Perennial Options In philosophy, two options are always available: primitivism and deflationism. Primitivism The primitivist theory says that truth is a primitive theres nothing more to say. Some Equivalences Snow is white is true Snow is white Snow is purple is true Snow is purple Michael is a philosopher is true Michael is a philosopher Michael is a shark is true Michael is a shark And so on Frank P. Ramsey Died at 26 Influential philosopher/ economist/ mathematician Created a branch of mathematics Ramsey Theory Good friend of Wittgenstein The Redundancy Theory of Truth Ramseys view of truth was that its true that p is just a fancy way of saying p. Is true is redundant. We dont need to say it, but we can if we have extra time on our hands. Virtue of Redundancy Saying something is true is not saying anything in addition to just saying that thing. So the question of what are the bearers of (the property of) truth? goes away: there is no property. Problems for Redundancy Consider the sentence what Michael said is true. Try to say this without is true. Attempt: Michael said poodles like noodles and poodles like noodles; OR Michael said lemurs have femurs and lemurs hate femurs; OR Michael said llamas star in dramas and llamas star in dramas; OR. Problems for Redundancy Consider the sentence everything Michael said is true. Try to say this without is true. Attempt: If Michael said poodles like noodles then poodles like noodles; AND If Michael said lemurs have femurs then lemurs hate femurs; AND If Michael said llamas star in dramas then llamas star in dramas; AND. Problems for Redundancy Consider the English sentence Der Schnee ist weiss is true Try to say this in English without is true. Attempt: If Der Schnee ist weiss translates to poodles like noodles then poodles like noodles; AND If Der Schnee ist weiss translates to lemurs have femurs then lemurs hate femurs; AND If Der Schnee ist weiss translates to llamas star in dramas then llamas star in dramas; AND. Deflationism The deflationist theory of truth says that truth is not redundant, but that is true is simply an expressive device. You could have a language with no is true that could say everything English can say. Infinitary Conjunction and Disjunction Everything Michael says is true: &{ p | if Michael says p, then p } That one thing Michael said is true: v{ p | Michael said p and p } Problems for Deflationism We began with the observation that true beliefs lead to successful actions. Why should this be so if is true is a dispensable expressive device.