15 ideas
23367 | Even pointing a finger should only be done for a reason [Epictetus] |
13917 | Metaphysics aims to identify categories of being, and show their interdependency [Lowe] |
13919 | Philosophy aims not at the 'analysis of concepts', but at understanding the essences of things [Lowe] |
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] |
13918 | Holes, shadows and spots of light can coincide without being identical [Lowe] |
13921 | All things must have an essence (a 'what it is'), or we would be unable to think about them [Lowe] |
13922 | Knowing an essence is just knowing what the thing is, not knowing some further thing [Lowe] |
13920 | Each thing has to be of a general kind, because it belongs to some category [Lowe] |