87 ideas
19579 | The history of philosophy is just experiments in how to do philosophy [Novalis] |
19583 | Philosophy only begins when it studies itself [Novalis] |
22026 | Philosophy is homesickness - the urge to be at home everywhere [Novalis] |
19588 | The highest aim of philosophy is to combine all philosophies into a unity [Novalis] |
19598 | Philosophy relies on our whole system of learning, and can thus never be complete [Novalis] |
19586 | Philosophers feed on problems, hoping they are digestible, and spiced with paradox [Novalis] |
19587 | Philosophy aims to produce a priori an absolute and artistic world system [Novalis] |
9108 | From an impossibility anything follows [William of Ockham] |
16676 | Why use more things when fewer will do? [William of Ockham] |
6806 | Do not multiply entities beyond necessity [William of Ockham] |
19574 | If man sacrifices truth he sacrifices himself, by acting against his own convictions [Novalis] |
9107 | A proposition is true if its subject and predicate stand for the same thing [William of Ockham] |
19571 | Delusion and truth differ in their life functions [Novalis] |
16300 | Ockham had an early axiomatic account of truth [William of Ockham, by Halbach] |
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] |
19597 | Logic (the theory of relations) should be applied to mathematics [Novalis] |
9106 | The word 'every' only signifies when added to a term such as 'man', referring to all men [William of Ockham] |
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] |
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] |
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] |
19581 | A problem is a solid mass, which the mind must break up [Novalis] |
13530 | An ordinal is an equivalence class of well-orderings, or a transitive set whose members are transitive [Wolf,RS] |
19584 | Whoever first counted to two must have seen the possibility of infinite counting [Novalis] |
13518 | Modern mathematics has unified all of its objects within set theory [Wolf,RS] |
9113 | Just as unity is not a property of a single thing, so numbers are not properties of many things [William of Ockham] |
9110 | The words 'thing' and 'to be' assert the same idea, as a noun and as a verb [William of Ockham] |
22025 | Novalis thought self-consciousness cannot disclose 'being', because we are temporal creatures [Novalis, by Pinkard] |
16608 | Ockham was an anti-realist about the categories [William of Ockham, by Pasnau] |
16654 | Our words and concepts don't always correspond to what is out there [William of Ockham] |
18529 | Relations are expressed either as absolute facts, or by a relational concept [William of Ockham] |
22132 | Species and genera are individual concepts which naturally signify many individuals [William of Ockham] |
9103 | A universal is not a real feature of objects, but only a thought-object in the mind [William of Ockham] |
15388 | Universals are single things, and only universal in what they signify [William of Ockham] |
16779 | Cut wood doesn't make a new substance, but seems to make separate subjects [William of Ockham] |
16757 | Hot water naturally cools down, which is due to the substantial form of the water [William of Ockham] |
16599 | Ockham says matter must be extended, so we don't need Quantity [William of Ockham, by Pasnau] |
16681 | Matter gets its quantity from condensation and rarefaction, which is just local motion [William of Ockham] |
19575 | Refinement of senses increasingly distinguishes individuals [Novalis] |
9109 | If essence and existence were two things, one could exist without the other, which is impossible [William of Ockham] |
16792 | If parts change, the whole changes [William of Ockham] |
9089 | Knowledge is a quality existing subjectively in the soul [William of Ockham] |
9091 | Sometimes 'knowledge' just concerns the conclusion, sometimes the whole demonstration [William of Ockham] |
9100 | Our intellect only assents to what we believe to be true [William of Ockham] |
9090 | Knowledge is certain cognition of something that is true [William of Ockham] |
22067 | Poetry is true idealism, and the self-consciousness of the universe [Novalis] |
19572 | Experiences tests reason, and reason tests experience [Novalis] |
19590 | Empiricists are passive thinkers, given their philosophy by the external world and fate [Novalis] |
19594 | General statements about nature are not valid [Novalis] |
9101 | Abstractive cognition knows universals abstracted from many singulars [William of Ockham] |
9102 | If an animal approached from a distance, we might abstract 'animal' from one instance [William of Ockham] |
19591 | Desire for perfection is an illness, if it turns against what is imperfect [Novalis] |
19596 | The whole body is involved in the formation of thoughts [Novalis] |
9114 | There are no secure foundations to prove the separate existence of mind, in reason or experience [William of Ockham] |
19573 | The seat of the soul is where our inner and outer worlds interpenetrate [Novalis] |
9104 | A universal is the result of abstraction, which is only a kind of mental picturing [William of Ockham] |
19577 | Everything is a chaotic unity, then we abstract, then we reunify the world into a free alliance [Novalis] |
9105 | Some concepts for propositions exist only in the mind, and in no language [William of Ockham] |
19585 | Every person has his own language [Novalis] |
19578 | Only self-illuminated perfect individuals are beautiful [Novalis] |
19582 | Morality and philosophy are mutually dependent [Novalis] |
22027 | Life isn't given to us like a novel - we write the novel [Novalis] |
19589 | The whole point of a monarch is that we accept them as a higher-born, ideal person [Novalis] |
19580 | If the pupil really yearns for the truth, they only need a hint [Novalis] |
19593 | Persons are shaped by a life history; splendid persons are shaped by world history [Novalis] |
19595 | Nature is a whole, and its individual parts cannot be wholly understood [Novalis] |
19592 | The basic relations of nature are musical [Novalis] |
16675 | Every extended material substance is composed of parts distant from one another [William of Ockham] |
19381 | The past has ceased to exist, and the future does not yet exist, so time does not exist [William of Ockham] |
9111 | God is not wise, but more-than-wise; God is not good, but more-than-good [William of Ockham] |
8010 | William of Ockham is the main spokesman for God's commands being the source of morality [William of Ockham] |
9112 | We could never form a concept of God's wisdom if we couldn't abstract it from creatures [William of Ockham] |
9115 | To love God means to love whatever God wills to be loved [William of Ockham] |
16679 | Even an angel must have some location [William of Ockham, by Pasnau] |
19576 | Religion needs an intermediary, because none of us can connect directly to a godhead [Novalis] |