92 ideas
7490 | Because of Darwin, wisdom as a definite attainable state has faded [Watson] |
7461 | The three key ideas are the soul, Europe, and the experiment [Watson] |
7464 | The big idea: imitation, the soul, experiments, God, heliocentric universe, evolution? [Watson] |
16325 | Analysis rests on natural language, but its ideal is a framework which revises language [Halbach] |
16292 | An explicit definition enables the elimination of what is defined [Halbach] |
7465 | Babylonian thinking used analogy, rather than deduction or induction [Watson] |
16307 | Don't trust analogies; they are no more than a guideline [Halbach] |
16339 | Truth axioms prove objects exist, so truth doesn't seem to be a logical notion [Halbach] |
16330 | Truth-value 'gluts' allow two truth values together; 'gaps' give a partial conception of truth [Halbach] |
16324 | Any definition of truth requires a metalanguage [Halbach] |
15647 | Truth definitions don't produce a good theory, because they go beyond your current language [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] |
15649 | In semantic theories of truth, the predicate is in an object-language, and the definition in a metalanguage [Halbach] |
16297 | Semantic theories avoid Tarski's Theorem by sticking to a sublanguage [Halbach] |
16337 | Disquotational truth theories are short of deductive power [Halbach] |
15648 | Instead of a truth definition, add a primitive truth predicate, and axioms for how it works [Halbach] |
15655 | Should axiomatic truth be 'conservative' - not proving anything apart from implications of the axioms? [Halbach] |
15654 | If truth is defined it can be eliminated, whereas axiomatic truth has various commitments [Halbach] |
16294 | Axiomatic truth doesn't presuppose a truth-definition, though it could admit it at a later stage [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] |
16326 | The main semantic theories of truth are Kripke's theory, and revisions semantics [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] |
16322 | CT proves PA consistent, which PA can't do on its own, so CT is not conservative over PA [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] |
15650 | Axiomatic theories of truth need a weak logical framework, and not a strong metatheory [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] |
16332 | The KF theory is useful, but it is not a theory containing its own truth predicate [Halbach] |
16329 | Kripke-Feferman theory KF axiomatises Kripke fixed-points, with Strong Kleene logic with gluts [Halbach] |
16331 | The KF is much stronger deductively than FS, which relies on classical truth [Halbach] |
15656 | Deflationists say truth merely serves to express infinite conjunctions [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] |
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] |
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] |
15657 | To prove the consistency of set theory, we must go beyond set theory [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] |
15652 | We can use truth instead of ontologically loaded second-order comprehension assumptions about properties [Halbach] |
15651 | Instead of saying x has a property, we can say a formula is true of x - as long as we have 'true' [Halbach] |
16310 | A theory is some formulae and all of their consequences [Halbach] |
16344 | Soundness must involve truth; the soundness of PA certainly needs it [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] |
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] |
7466 | Mesopotamian numbers applied to specific things, and then became abstract [Watson] |
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] |
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] |
16346 | Maybe necessity is a predicate, not the usual operator, to make it more like truth [Halbach] |
20657 | There are 23 core brain functions, with known circuit, transmitters, genes and behaviour [Watson] |
20656 | Traditional ideas of the mind were weakened in the 1950s by mind-influencing drugs [Watson] |
16298 | We need propositions to ascribe the same beliefs to people with different languages [Halbach] |
20655 | Humans have been hunter-gatherers for 99.5% of their existence [Watson] |
7346 | Jeremiah implied a link between weakness and goodness, and the evil of the state [Jeremiah, by Johnson,P] |
7477 | Modern democracy is actually elective oligarchy [Watson] |
7478 | Greek philosophers invented the concept of 'nature' as their special subject [Watson] |
20650 | The Uncertainty Principle implies that cause and effect can't be measured [Watson] |
20649 | The interference of light through two slits confirmed that it is waves [Watson] |
20661 | Electrons rotate in hyrogen atoms 10^13 times per second [Watson] |
20647 | Quantum theory explains why nature is made up of units, such as elements [Watson] |
20654 | Only four particles are needed for matter: up and down quark, electron, electron-neutrino [Watson] |
20651 | The shape of molecules is important, as well as the atoms and their bonds [Watson] |
20652 | In 1828 the animal substance urea was manufactured from inorganic ingredients [Watson] |
20658 | Information is physical, and living can be seen as replicating and preserving information [Watson] |
7462 | DNA mutation suggests humans and chimpanzees diverged 6.6 million years ago [Watson] |
22920 | Do I not fill heaven and earth? saith the Lord [Jeremiah] |
22089 | Am I a God afar off, and not a God close at hand? [Jeremiah] |
7470 | During the rise of civilizations, the main gods changed from female to male [Watson] |
7474 | Hinduism has no founder, or prophet, or creed, or ecclesiastical structure [Watson] |
7480 | Monotheism was a uniquely Israelite creation within the Middle East [Watson] |
7479 | Modern Judaism became stabilised in 200 CE [Watson] |
7481 | The Israelites may have asserted the uniqueness of Yahweh to justify land claims [Watson] |
7471 | The Gathas (hymns) of Zoroastrianism date from about 1000 BCE [Watson] |
7473 | Zoroaster conceived the afterlife, judgement, heaven and hell, and the devil [Watson] |
7483 | Paul's early writings mention few striking episodes from Jesus' life [Watson] |
7484 | Jesus never intended to start a new religion [Watson] |
7475 | Confucius revered the spiritual world, but not the supernatural, or a personal god, or the afterlife [Watson] |
7476 | Taoism aims at freedom from the world, the body, the mind, and nature [Watson] |
7463 | The three basic ingredients of religion are: the soul, seers or priests, and ritual [Watson] |
7468 | In ancient Athens the souls of the dead are received by the 'upper air' [Watson] |