25 ideas
13838 | A decent modern definition should always imply a semantics [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] |
13833 | 'Thinning' ('dilution') is the key difference between deduction (which allows it) and induction [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] |
14329 | Some dispositional properties (such as mental ones) may have no categorical base [Price,HH] |
8830 | A belief can be justified when the person has forgotten the evidence for it [Goldman] |
8832 | If justified beliefs are well-formed beliefs, then animals and young children have them [Goldman] |
8829 | Justification depends on the reliability of its cause, where reliable processes tend to produce truth [Goldman] |
9032 | Before we can abstract from an instance of violet, we must first recognise it [Price,HH] |
9034 | There may be degrees of abstraction which allow recognition by signs, without full concepts [Price,HH] |
9035 | If judgement of a characteristic is possible, that part of abstraction must be complete [Price,HH] |
9036 | There is pre-verbal sign-based abstraction, as when ice actually looks cold [Price,HH] |
9037 | Intelligent behaviour, even in animals, has something abstract about it [Price,HH] |
8831 | Introspection is really retrospection; my pain is justified by a brief causal history [Goldman] |
9033 | Recognition must precede the acquisition of basic concepts, so it is the fundamental intellectual process [Price,HH] |
9030 | Abstractions can be interpreted dispositionally, as the ability to recognise or imagine an item [Price,HH] |
9029 | If ideas have to be images, then abstract ideas become a paradoxical problem [Price,HH] |
9031 | The basic concepts of conceptual cognition are acquired by direct abstraction from instances [Price,HH] |