17 ideas
2676 | Didactic argument starts from the principles of the subject, not from the opinions of the learner [Aristotle] |
2675 | Reasoning is a way of making statements which makes them lead on to other statements [Aristotle] |
2677 | Dialectic aims to start from generally accepted opinions, and lead to a contradiction [Aristotle] |
2674 | Competitive argument aims at refutation, fallacy, paradox, solecism or repetition [Aristotle] |
13913 | The four 'perfect syllogisms' are called Barbara, Celarent, Darii and Ferio [Engelbretsen/Sayward] |
13914 | Syllogistic logic has one rule: what is affirmed/denied of wholes is affirmed/denied of their parts [Engelbretsen/Sayward] |
13915 | Syllogistic can't handle sentences with singular terms, or relational terms, or compound sentences [Engelbretsen/Sayward] |
13916 | Term logic uses expression letters and brackets, and '-' for negative terms, and '+' for compound terms [Engelbretsen/Sayward] |
13850 | In modern logic all formal validity can be characterised syntactically [Engelbretsen/Sayward] |
13849 | Classical logic rests on truth and models, where constructivist logic rests on defence and refutation [Engelbretsen/Sayward] |
13851 | Unlike most other signs, = cannot be eliminated [Engelbretsen/Sayward] |
16967 | 'Are Coriscus and Callias at home?' sounds like a single question, but it isn't [Aristotle] |
13852 | Axioms are ω-incomplete if the instances are all derivable, but the universal quantification isn't [Engelbretsen/Sayward] |
16149 | Generic terms like 'man' are not substances, but qualities, relations, modes or some such thing [Aristotle] |
11840 | Only if two things are identical do they have the same attributes [Aristotle] |
1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |