33 ideas
13838 | A decent modern definition should always imply a semantics [Hacking] |
13833 | 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [Hacking] |
13834 | Gentzen's Cut Rule (or transitivity of deduction) is 'If A |- B and B |- C, then A |- C' [Hacking] |
13835 | Only Cut reduces complexity, so logic is constructive without it, and it can be dispensed with [Hacking] |
13845 | The various logics are abstractions made from terms like 'if...then' in English [Hacking] |
13840 | First-order logic is the strongest complete compact theory with Löwenheim-Skolem [Hacking] |
13844 | A limitation of first-order logic is that it cannot handle branching quantifiers [Hacking] |
13842 | Second-order completeness seems to need intensional entities and possible worlds [Hacking] |
13837 | With a pure notion of truth and consequence, the meanings of connectives are fixed syntactically [Hacking] |
13839 | Perhaps variables could be dispensed with, by arrows joining places in the scope of quantifiers [Hacking] |
13843 | If it is a logic, the Löwenheim-Skolem theorem holds for it [Hacking] |
16665 | There are entities, and then positive 'modes', modifying aspects outside the thing's essence [Suárez] |
16666 | A mode determines the state and character of a quantity, without adding to it [Suárez] |
16667 | Substances are incomplete unless they have modes [Suárez, by Pasnau] |
17007 | Forms must rule over faculties and accidents, and are the source of action and unity [Suárez] |
16780 | Partial forms of leaf and fruit are united in the whole form of the tree [Suárez] |
16758 | The best support for substantial forms is the co-ordinated unity of a natural being [Suárez] |
16743 | We can get at the essential nature of 'quantity' by knowing bulk and extension [Suárez] |
16742 | We only know essences through non-essential features, esp. those closest to the essence [Suárez] |
22143 | Identity does not exclude possible or imagined difference [Suárez, by Boulter] |
22144 | Real Essential distinction: A and B are of different natural kinds [Suárez, by Boulter] |
22146 | Minor Real distinction: B needs A, but A doesn't need B [Suárez, by Boulter] |
22145 | Major Real distinction: A and B have independent existences [Suárez, by Boulter] |
22147 | Conceptual/Mental distinction: one thing can be conceived of in two different ways [Suárez, by Boulter] |
22148 | Modal distinction: A isn't B or its property, but still needs B [Suárez, by Boulter] |
22149 | Scholastics assess possibility by what has actually happened in reality [Suárez, by Boulter] |
21515 | Incoherence may be more important for enquiry than coherence [Olsson] |
21514 | Coherence is the capacity to answer objections [Olsson] |
21496 | Mere agreement of testimonies is not enough to make truth very likely [Olsson] |
21499 | Coherence is only needed if the information sources are not fully reliable [Olsson] |
21502 | A purely coherent theory cannot be true of the world without some contact with the world [Olsson] |
21512 | Extending a system makes it less probable, so extending coherence can't make it more probable [Olsson] |
16682 | Other things could occupy the same location as an angel [Suárez] |