31 ideas
9208 | Philosophers with a new concept are like children with a new toy [Fine,K] |
16877 | A 'constructive' (as opposed to 'analytic') definition creates a new sign [Frege] |
11219 | Frege suggested that mathematics should only accept stipulative definitions [Frege, by Gupta] |
16878 | We must be clear about every premise and every law used in a proof [Frege] |
16867 | Logic not only proves things, but also reveals logical relations between them [Frege] |
16863 | Does some mathematical reasoning (such as mathematical induction) not belong to logic? [Frege] |
16862 | The closest subject to logic is mathematics, which does little apart from drawing inferences [Frege] |
16865 | 'Theorems' are both proved, and used in proofs [Frege] |
16866 | Tracing inference backwards closes in on a small set of axioms and postulates [Frege] |
16868 | The essence of mathematics is the kernel of primitive truths on which it rests [Frege] |
16871 | A truth can be an axiom in one system and not in another [Frege] |
16870 | Axioms are truths which cannot be doubted, and for which no proof is needed [Frege] |
16869 | To create order in mathematics we need a full system, guided by patterns of inference [Frege] |
16864 | If principles are provable, they are theorems; if not, they are axioms [Frege] |
9210 | Possible objects are abstract; actual concrete objects are possible; so abstract/concrete are compatible [Fine,K] |
9211 | A non-standard realism, with no privileged standpoint, might challenge its absoluteness or coherence [Fine,K] |
9202 | Objects, as well as sentences, can have logical form [Fine,K] |
9388 | Every concept must have a sharp boundary; we cannot allow an indeterminate third case [Frege] |
9206 | We must distinguish between the identity or essence of an object, and its necessary features [Fine,K] |
9205 | The three basic types of necessity are metaphysical, natural and normative [Fine,K] |
9209 | Metaphysical necessity may be 'whatever the circumstance', or 'regardless of circumstances' [Fine,K] |
9200 | Empiricists suspect modal notions: either it happens or it doesn't; it is just regularities. [Fine,K] |
16876 | We need definitions to cram retrievable sense into a signed receptacle [Frege] |
16875 | We use signs to mark receptacles for complex senses [Frege] |
16879 | A sign won't gain sense just from being used in sentences with familiar components [Frege] |
9207 | If sentence content is all worlds where it is true, all necessary truths have the same content! [Fine,K] |
16873 | Thoughts are not subjective or psychological, because some thoughts are the same for us all [Frege] |
16872 | A thought is the sense expressed by a sentence, and is what we prove [Frege] |
16874 | The parts of a thought map onto the parts of a sentence [Frege] |
1472 | The propositions that God is good and omnipotent, and that evil exists, are logically contradictory [Mackie, by PG] |
1473 | Is evil an illusion, or a necessary contrast, or uncontrollable, or necessary for human free will? [Mackie, by PG] |