80 ideas
1606 | You have to be a Platonist to debate about reality, so every philosopher is a Platonist [Roochnik] |
1595 | Philosophy aims to satisfy the chief human desire - the articulation of beauty itself [Roochnik] |
16325 | Analysis rests on natural language, but its ideal is a framework which revises language [Halbach] |
1571 | 'Logos' ranges from thought/reasoning, to words, to rational structures outside thought [Roochnik] |
1572 | In the seventeenth century the only acceptable form of logos was technical knowledge [Roochnik] |
1573 | The hallmark of a person with logos is that they give reasons why one opinion is superior to another [Roochnik] |
1592 | Logos cannot refute the relativist, and so must admit that it too is a matter of desire (for truth and agreement) [Roochnik] |
1593 | Human desire has an ordered structure, with logos at the pinnacle [Roochnik] |
1603 | Logos is not unconditionally good, but good if there is another person willing to engage with it [Roochnik] |
1598 | We prefer reason or poetry according to whether basics are intelligible or not [Roochnik] |
1584 | Modern science, by aiming for clarity about the external world, has abandoned rationality in the human world [Roochnik] |
1591 | Unfortunately for reason, argument can't be used to establish the value of argument [Roochnik] |
1599 | Attempts to suspend all presuppositions are hopeless, because a common ground must be agreed for the process [Roochnik] |
16292 | An explicit definition enables the elimination of what is defined [Halbach] |
16307 | Don't trust analogies; they are no more than a guideline [Halbach] |
16330 | Truth-value 'gluts' allow two truth values together; 'gaps' give a partial conception of truth [Halbach] |
16339 | Truth axioms prove objects exist, so truth doesn't seem to be a logical notion [Halbach] |
16324 | Any definition of truth requires a metalanguage [Halbach] |
16293 | Traditional definitions of truth often make it more obscure, rather than less [Halbach] |
16301 | If people have big doubts about truth, a definition might give it more credibility [Halbach] |
16297 | Semantic theories avoid Tarski's Theorem by sticking to a sublanguage [Halbach] |
16337 | Disquotational truth theories are short of deductive power [Halbach] |
16322 | CT proves PA consistent, which PA can't do on its own, so CT is not conservative over PA [Halbach] |
16294 | Axiomatic truth doesn't presuppose a truth-definition, though it could admit it at a later stage [Halbach] |
16326 | The main semantic theories of truth are Kripke's theory, and revisions semantics [Halbach] |
16311 | To axiomatise Tarski's truth definition, we need a binary predicate for his 'satisfaction' [Halbach] |
16318 | Compositional Truth CT has the truth of a sentence depending of the semantic values of its constituents [Halbach] |
16299 | Gödel numbering means a theory of truth can use Peano Arithmetic as its base theory [Halbach] |
16340 | Truth axioms need a base theory, because that is where truth issues arise [Halbach] |
16305 | We know a complete axiomatisation of truth is not feasible [Halbach] |
16313 | A theory is 'conservative' if it adds no new theorems to its base theory [Halbach, by PG] |
16315 | The Tarski Biconditional theory TB is Peano Arithmetic, plus truth, plus all Tarski bi-conditionals [Halbach] |
16314 | Theories of truth are 'typed' (truth can't apply to sentences containing 'true'), or 'type-free' [Halbach] |
16327 | Friedman-Sheard is type-free Compositional Truth, with two inference rules for truth [Halbach] |
16329 | Kripke-Feferman theory KF axiomatises Kripke fixed-points, with Strong Kleene logic with gluts [Halbach] |
16332 | The KF theory is useful, but it is not a theory containing its own truth predicate [Halbach] |
16331 | The KF is much stronger deductively than FS, which relies on classical truth [Halbach] |
16319 | Compositional Truth CT proves generalisations, so is preferred in discussions of deflationism [Halbach] |
16320 | Some say deflationism is axioms which are conservative over the base theory [Halbach] |
16338 | Deflationism says truth is a disquotation device to express generalisations, adding no new knowledge [Halbach] |
16317 | The main problem for deflationists is they can express generalisations, but not prove them [Halbach] |
16316 | Deflationists say truth is just for expressing infinite conjunctions or generalisations [Halbach] |
16335 | In Strong Kleene logic a disjunction just needs one disjunct to be true [Halbach] |
16334 | In Weak Kleene logic there are 'gaps', neither true nor false if one component lacks a truth value [Halbach] |
16309 | Every attempt at formal rigour uses some set theory [Halbach] |
16333 | The underestimated costs of giving up classical logic are found in mathematical reasoning [Halbach] |
16310 | A theory is some formulae and all of their consequences [Halbach] |
16342 | You cannot just say all of Peano arithmetic is true, as 'true' isn't part of the system [Halbach] |
16341 | Normally we only endorse a theory if we believe it to be sound [Halbach] |
16344 | Soundness must involve truth; the soundness of PA certainly needs it [Halbach] |
16347 | Many new paradoxes may await us when we study interactions between frameworks [Halbach] |
16336 | The liar paradox applies truth to a negated truth (but the conditional will serve equally) [Halbach] |
16321 | The compactness theorem can prove nonstandard models of PA [Halbach] |
16343 | The global reflection principle seems to express the soundness of Peano Arithmetic [Halbach] |
16312 | To reduce PA to ZF, we represent the non-negative integers with von Neumann ordinals [Halbach] |
17536 | If it can't be expressed mathematically, it can't occur in nature? [Heisenberg] |
16308 | Set theory was liberated early from types, and recent truth-theories are exploring type-free [Halbach] |
16345 | That Peano arithmetic is interpretable in ZF set theory is taken by philosophers as a reduction [Halbach] |
17545 | Quantum theory shows that exact science does not need dogmatic realism [Heisenberg] |
1605 | Reality can be viewed neutrally, or as an object of desire [Roochnik] |
17538 | Quantum theory does not introduce minds into atomic events [Heisenberg] |
17534 | A 'probability wave' is a quantitative version of Aristotle's potential, a mid-way type of reality [Heisenberg] |
17553 | We can retain the idea of 'substance', as indestructible mass or energy [Heisenberg] |
17544 | Basic particles have a mathematical form, which is more important than their substance [Heisenberg] |
16346 | Maybe necessity is a predicate, not the usual operator, to make it more like truth [Halbach] |
1577 | Relativism is a disease which destroys the possibility of rational debate [Roochnik] |
17550 | We give a mathematical account of a system of natural connections in order to clarify them [Heisenberg] |
16298 | We need propositions to ascribe the same beliefs to people with different languages [Halbach] |
1578 | If relativism is the correct account of human values, then rhetoric is more important than reasoning [Roochnik] |
1596 | Reasoning aims not at the understanding of objects, but at the desire to give beautiful speeches [Roochnik] |
17549 | Seven theories in science: mechanics, heat, electricity, quantum, particles, relativity, life [Heisenberg, by PG] |
17540 | Energy is that which moves, and is the substance from which everything is made [Heisenberg] |
17541 | Energy is an unchanging substance, having many forms, and causing all change [Heisenberg] |
17548 | Maxwell introduced real fields, which transferred forces from point to point [Heisenberg] |
17533 | Radiation interference needs waves, but radiation photoelectric effects needs particles [Heisenberg] |
17532 | An atom's stability after collisions needs explaining (which Newton's mechanics can't do) [Heisenberg] |
17537 | Position is complementary to velocity or momentum, so the whole system is indeterminate [Heisenberg] |
17551 | It was formerly assumed that electromagnetic waves could not be a reality in themselves [Heisenberg] |
17543 | So-called 'empty' space is the carrier of geometry and kinematics [Heisenberg] |
17552 | In relativity the length of the 'present moment' is relative to distance from the observer [Heisenberg] |