12 ideas
13917 | Metaphysics aims to identify categories of being, and show their interdependency [Lowe] |
13919 | Philosophy aims not at the 'analysis of concepts', but at understanding the essences of things [Lowe] |
11022 | Gentzen introduced a natural deduction calculus (NK) in 1934 [Gentzen, by Read] |
11065 | The inferential role of a logical constant constitutes its meaning [Gentzen, by Hanna] |
11023 | The logical connectives are 'defined' by their introduction rules [Gentzen] |
11213 | Each logical symbol has an 'introduction' rule to define it, and hence an 'elimination' rule [Gentzen] |
10067 | Gentzen proved the consistency of arithmetic from assumptions beyond arithmetic [Gentzen, by Musgrave] |
13918 | Holes, shadows and spots of light can coincide without being identical [Lowe] |
13921 | All things must have an essence (a 'what it is'), or we would be unable to think about them [Lowe] |
13922 | Knowing an essence is just knowing what the thing is, not knowing some further thing [Lowe] |
13920 | Each thing has to be of a general kind, because it belongs to some category [Lowe] |
22406 | The maximisation of happiness must be done fairly [Rawls, by Smart] |