32 ideas
2666 | Carneades' pinnacles of philosophy are the basis of knowledge (the criterion of truth) and the end of appetite (good) [Carneades, by Cicero] |
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] |
21390 | Future events are true if one day we will say 'this event is happening now' [Carneades] |
21672 | We say future things are true that will possess actuality at some following time [Carneades, by Cicero] |
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] |
9388 | Every concept must have a sharp boundary; we cannot allow an indeterminate third case [Frege] |
15825 | Carneades denied the transitivity of identity [Carneades, by Chisholm] |
21389 | Carneades distinguished logical from causal necessity, when talking of future events [Long on Carneades] |
21671 | Voluntary motion is intrinsically within our power, and this power is its cause [Carneades, by Cicero] |
21391 | Some actions are within our power; determinism needs prior causes for everything - so it is false [Carneades, by Cicero] |
21674 | Even Apollo can only foretell the future when it is naturally necessary [Carneades, by Cicero] |
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] |
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] |
7398 | Carneades said that after a shipwreck a wise man would seize the only plank by force [Carneades, by Tuck] |
21392 | People change laws for advantage; either there is no justice, or it is a form of self-injury [Carneades, by Lactantius] |
16713 | Philosophers are the forefathers of heretics [Tertullian] |
6610 | I believe because it is absurd [Tertullian] |