4 ideas
15927 | Definition just needs negation, known variables, conjunction, disjunction, substitution and quantification [Weyl, by Lavine] |
18948 | There is an object for every set of properties (some of which exist, and others don't) [Parsons,T, by Sawyer] |
20653 | Six reduction levels: groups, lives, cells, molecules, atoms, particles [Putnam/Oppenheim, by Watson] |
10246 | The limit of science is isomorphism of theories, with essences a matter of indifference [Weyl] |