15 ideas
10688 | 'Equivocation' is when terms do not mean the same thing in premises and conclusion [Beall/Restall] |
10690 | Formal logic is invariant under permutations, or devoid of content, or gives the norms for thought [Beall/Restall] |
10691 | Logical consequence needs either proofs, or absence of counterexamples [Beall/Restall] |
10695 | Logical consequence is either necessary truth preservation, or preservation based on interpretation [Beall/Restall] |
10689 | A step is a 'material consequence' if we need contents as well as form [Beall/Restall] |
10696 | A 'logical truth' (or 'tautology', or 'theorem') follows from empty premises [Beall/Restall] |
10693 | Models are mathematical structures which interpret the non-logical primitives [Beall/Restall] |
10692 | Hilbert proofs have simple rules and complex axioms, and natural deduction is the opposite [Beall/Restall] |
12312 | The real essence of a thing is its powers, or 'dispositional properties' [Copi] |
10937 | Essential properties are the 'deepest' ones which explain the others [Copi, by Rami] |
12308 | In modern science, nominal essence is intended to be real essence [Copi] |
12694 | Essence is the distinct thinkability of anything [Leibniz] |
12303 | Within the four types of change, essential attributes are those whose loss means destruction [Copi] |
12307 | Modern science seeks essences, and is getting closer to them [Copi] |
12310 | Real essences are scientifically knowable, but so are non-essential properties [Copi] |