45 ideas
5333 | Philosophy needs wisdom about who we are, as well as how we ought to be [Flanagan] |
5334 | We resist science partly because it can't provide ethical wisdom [Flanagan] |
13520 | A 'tautology' must include connectives [Wolf,RS] |
13524 | Deduction Theorem: T∪{P}|-Q, then T|-(P→Q), which justifies Conditional Proof [Wolf,RS] |
13522 | Universal Generalization: If we prove P(x) with no special assumptions, we can conclude ∀xP(x) [Wolf,RS] |
13521 | Universal Specification: ∀xP(x) implies P(t). True for all? Then true for an instance [Wolf,RS] |
13523 | Existential Generalization (or 'proof by example'): if we can say P(t), then we can say something is P [Wolf,RS] |
13529 | Empty Set: ∃x∀y ¬(y∈x). The unique empty set exists [Wolf,RS] |
13526 | Comprehension Axiom: if a collection is clearly specified, it is a set [Wolf,RS] |
13534 | In first-order logic syntactic and semantic consequence (|- and |=) nicely coincide [Wolf,RS] |
13535 | First-order logic is weakly complete (valid sentences are provable); we can't prove every sentence or its negation [Wolf,RS] |
13531 | Model theory reveals the structures of mathematics [Wolf,RS] |
13532 | Model theory 'structures' have a 'universe', some 'relations', some 'functions', and some 'constants' [Wolf,RS] |
13519 | Model theory uses sets to show that mathematical deduction fits mathematical truth [Wolf,RS] |
13533 | First-order model theory rests on completeness, compactness, and the Löwenheim-Skolem-Tarski theorem [Wolf,RS] |
13537 | An 'isomorphism' is a bijection that preserves all structural components [Wolf,RS] |
13539 | The LST Theorem is a serious limitation of first-order logic [Wolf,RS] |
13538 | If a theory is complete, only a more powerful language can strengthen it [Wolf,RS] |
13525 | Most deductive logic (unlike ordinary reasoning) is 'monotonic' - we don't retract after new givens [Wolf,RS] |
13530 | An ordinal is an equivalence class of well-orderings, or a transitive set whose members are transitive [Wolf,RS] |
13518 | Modern mathematics has unified all of its objects within set theory [Wolf,RS] |
5340 | Explanation does not entail prediction [Flanagan] |
5346 | In the 17th century a collisionlike view of causation made mental causation implausible [Flanagan] |
5341 | Only you can have your subjective experiences because only you are hooked up to your nervous system [Flanagan] |
5351 | We only have a sense of our self as continuous, not as exactly the same [Flanagan] |
5353 | The self is an abstraction which magnifies important aspects of autobiography [Flanagan] |
5354 | We are not born with a self; we develop a self through living [Flanagan] |
5349 | For Buddhists a fixed self is a morally dangerous illusion [Flanagan] |
5338 | Normal free will claims control of what I do, but a stronger view claims control of thought and feeling [Flanagan] |
5344 | Free will is held to give us a whole list of desirable capacities for living [Flanagan] |
5332 | People believe they have free will that circumvents natural law, but only an incorporeal mind could do this [Flanagan] |
5345 | We only think of ourselves as having free will because we first thought of God that way [Flanagan] |
5343 | People largely came to believe in dualism because it made human agents free [Flanagan] |
5347 | Behaviourism notoriously has nothing to say about mental causation [Flanagan] |
5339 | Cars and bodies obey principles of causation, without us knowing any 'strict laws' about them [Flanagan] |
5342 | Physicalism doesn't deny that the essence of an experience is more than its neural realiser [Flanagan] |
5335 | Emotions are usually very apt, rather than being non-rational and fickle [Flanagan] |
5348 | Intellectualism admires the 'principled actor', non-intellectualism admires the 'good character' [Flanagan] |
5355 | Cognitivists think morals are discovered by reason [Flanagan] |
5336 | Ethics is the science of the conditions that lead to human flourishing [Flanagan] |
5049 | Intelligent pleasure is the perception of beauty, order and perfection [Leibniz] |
5048 | Perfection is simply quantity of reality [Leibniz] |
5350 | The Hindu doctrine of reincarnation only appeared in the eighth century CE [Flanagan] |
5352 | The idea of the soul gets some support from the scientific belief in essential 'natural kinds' [Flanagan] |
5050 | Evil serves a greater good, and pain is necessary for higher pleasure [Leibniz] |