15 ideas
| 20728 | Metaphysics is hopeless with its present epistemology; common-sense realism is needed [Colvin] |
| 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] |
| 13852 | Axioms are ω-incomplete if the instances are all derivable, but the universal quantification isn't [Engelbretsen/Sayward] |
| 20726 | We can only distinguish self from non-self if there is an inflexible external reality [Colvin] |
| 20727 | Common-sense realism rests on our interests and practical life [Colvin] |
| 20730 | If objects are doubted because their appearances change, that presupposes one object [Colvin] |
| 20729 | Arguments that objects are unknowable or non-existent assume the knower's existence [Colvin] |
| 20731 | The idea that everything is relations is contradictory; relations are part of the concept of things [Colvin] |
| 21229 | If everyone is treated with equal injustice, at least that is fair [Morgenbesser] |