30 ideas
4643 | The Principle of Sufficient Reason does not presuppose that all explanations will be causal explanations [Baggini /Fosl] |
4633 | You cannot rationally deny the principle of non-contradiction, because all reasoning requires it [Baggini /Fosl] |
4635 | Dialectic aims at unified truth, unlike analysis, which divides into parts [Baggini /Fosl] |
4632 | 'Natural' systems of deduction are based on normal rational practice, rather than on axioms [Baggini /Fosl] |
4631 | In ideal circumstances, an axiom should be such that no rational agent could possibly object to its use [Baggini /Fosl] |
13010 | In order to select the logic justified by experience, we would need to use a lot of logic [Boghossian on Quine] |
9002 | Elementary logic requires truth-functions, quantifiers (and variables), identity, and also sets of variables [Quine] |
13681 | Logical consequence is marked by being preserved under all nonlogical substitutions [Quine, by Sider] |
4638 | The principle of bivalence distorts reality, as when claiming that a person is or is not 'thin' [Baggini /Fosl] |
13829 | If logical truths essentially depend on logical constants, we had better define the latter [Hacking on Quine] |
9003 | Set theory was struggling with higher infinities, when new paradoxes made it baffling [Quine] |
9004 | If set theory is not actually a branch of logic, then Frege's derivation of arithmetic would not be from logic [Quine] |
19400 | Possibles demand existence, so as many of them as possible must actually exist [Leibniz] |
19401 | God's sufficient reason for choosing reality is in the fitness or perfection of possibilities [Leibniz] |
9006 | Commitment to universals is as arbitrary or pragmatic as the adoption of a new system of bookkeeping [Quine] |
4640 | If identity is based on 'true of X' instead of 'property of X' we get the Masked Man fallacy ('I know X but not Y') [Baggini /Fosl, by PG] |
4647 | 'I have the same car as you' is fine; 'I have the same fiancée as you' is not so good [Baggini /Fosl] |
4639 | Leibniz's Law is about the properties of objects; the Identity of Indiscernibles is about perception of objects [Baggini /Fosl] |
4646 | Is 'events have causes' analytic a priori, synthetic a posteriori, or synthetic a priori? [Baggini /Fosl] |
9001 | Frege moved Kant's question about a priori synthetic to 'how is logical certainty possible?' [Quine] |
19402 | The actual universe is the richest composite of what is possible [Leibniz] |
4645 | 'A priori' does not concern how you learn a proposition, but how you show whether it is true or false [Baggini /Fosl] |
9005 | Examination of convention in the a priori begins to blur the distinction with empirical knowledge [Quine] |
4582 | Basic beliefs are self-evident, or sensual, or intuitive, or revealed, or guaranteed [Baggini /Fosl] |
4644 | A proposition such as 'some swans are purple' cannot be falsified, only verified [Baggini /Fosl] |
4584 | The problem of induction is how to justify our belief in the uniformity of nature [Baggini /Fosl] |
4583 | How can an argument be good induction, but poor deduction? [Baggini /Fosl] |
4634 | Abduction aims at simplicity, testability, coherence and comprehensiveness [Baggini /Fosl] |
4637 | To see if an explanation is the best, it is necessary to investigate the alternative explanations [Baggini /Fosl] |
4629 | Consistency is the cornerstone of rationality [Baggini /Fosl] |