12 ideas
| 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] |
| 16886 | The truth of an axiom must be independently recognisable [Frege] |
| 10067 | Gentzen proved the consistency of arithmetic from assumptions beyond arithmetic [Gentzen, by Musgrave] |
| 5673 | If we have a pain, we are strongly aware of the bodily self [Cassam] |
| 5670 | Knowledge of thoughts covers both their existence and their contents [Cassam] |
| 5671 | Outer senses are as important as introspection in the acquisition of self-knowledge [Cassam] |
| 5672 | Is there a mode of self-awareness that isn't perception, and could it give self-knowledge? [Cassam] |
| 5675 | Neither self-consciousness nor self-reference require self-knowledge [Cassam] |
| 5674 | We can't introspect ourselves as objects, because that would involve possible error [Cassam] |