57 ideas
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] |
10476 | The idea that groups of concepts could be 'implicitly defined' was abandoned [Hodges,W] |
9107 | A proposition is true if its subject and predicate stand for the same thing [William of Ockham] |
16300 | Ockham had an early axiomatic account of truth [William of Ockham, by Halbach] |
10282 | Logic is the study of sound argument, or of certain artificial languages (or applying the latter to the former) [Hodges,W] |
10478 | Since first-order languages are complete, |= and |- have the same meaning [Hodges,W] |
10477 | |= in model-theory means 'logical consequence' - it holds in all models [Hodges,W] |
9106 | The word 'every' only signifies when added to a term such as 'man', referring to all men [William of Ockham] |
10283 | A formula needs an 'interpretation' of its constants, and a 'valuation' of its variables [Hodges,W] |
10284 | There are three different standard presentations of semantics [Hodges,W] |
10285 | I |= φ means that the formula φ is true in the interpretation I [Hodges,W] |
10474 | |= should be read as 'is a model for' or 'satisfies' [Hodges,W] |
10473 | Model theory studies formal or natural language-interpretation using set-theory [Hodges,W] |
10475 | A 'structure' is an interpretation specifying objects and classes of quantification [Hodges,W] |
10481 | Models in model theory are structures, not sets of descriptions [Hodges,W] |
10288 | Down Löwenheim-Skolem: if a countable language has a consistent theory, that has a countable model [Hodges,W] |
10289 | Up Löwenheim-Skolem: if infinite models, then arbitrarily large models [Hodges,W] |
10287 | If a first-order theory entails a sentence, there is a finite subset of the theory which entails it [Hodges,W] |
10480 | First-order logic can't discriminate between one infinite cardinal and another [Hodges,W] |
10286 | A 'set' is a mathematically well-behaved class [Hodges,W] |
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] |
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] |
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] |
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] |
2170 | Homer does not distinguish between soul and body [Homer, by Williams,B] |
9114 | There are no secure foundations to prove the separate existence of mind, in reason or experience [William of Ockham] |
9104 | A universal is the result of abstraction, which is only a kind of mental picturing [William of Ockham] |
9105 | Some concepts for propositions exist only in the mind, and in no language [William of Ockham] |
2171 | The 'will' doesn't exist; there is just conclusion, then action [Homer, by Williams,B] |
21819 | Plato says the Good produces the Intellectual-Principle, which in turn produces the Soul [Homer, by Plotinus] |
11388 | Let there be one ruler [Homer] |
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] |
14829 | Homer so enjoys the company of the gods that he must have been deeply irreligious [Homer, by Nietzsche] |
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] |