43 ideas
| 18290 | But what is the reasoning of the body, that it requires the wisdom you seek? [Nietzsche] |
| 18303 | Reject wisdom that lacks laughter [Nietzsche] |
| 18305 | To love truth, you must know how to lie [Nietzsche] |
| 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] |
| 20757 | The powerful self behind your thoughts and feelings is your body [Nietzsche] |
| 18289 | Forget the word 'I'; 'I' is performed by the intelligence of your body [Nietzsche] |
| 18299 | The will is constantly frustrated by the past [Nietzsche] |
| 18297 | We created meanings, to maintain ourselves [Nietzsche] |
| 18293 | The noble man wants new virtues; the good man preserves what is old [Nietzsche] |
| 18301 | We only really love children and work [Nietzsche] |
| 18307 | I want my work, not happiness! [Nietzsche] |
| 7903 | The six perfections are giving, morality, patience, vigour, meditation, and wisdom [Nagarjuna] |
| 18291 | Virtues can destroy one another, through jealousy [Nietzsche] |
| 18287 | People now find both wealth and poverty too much of a burden [Nietzsche] |
| 18295 | If you want friends, you must be a fighter [Nietzsche] |
| 18286 | The greatest experience possible is contempt for your own happiness, reason and virtue [Nietzsche] |
| 18296 | An enduring people needs its own individual values [Nietzsche] |
| 18294 | The state coldly claims that it is the people, but that is a lie [Nietzsche] |
| 18304 | Saints want to live as they desire, or not to live at all [Nietzsche] |
| 18300 | Whenever we have seen suffering, we have wanted the revenge of punishment [Nietzsche] |
| 18302 | Man and woman are deeply strange to one another! [Nietzsche] |
| 18292 | I can only believe in a God who can dance [Nietzsche] |
| 18298 | Not being a god is insupportable, so there are no gods! [Nietzsche] |
| 18288 | Heaven was invented by the sick and the dying [Nietzsche] |
| 18306 | We don't want heaven; now that we are men, we want the kingdom of earth [Nietzsche] |