Ideas of Engelbretsen,G/Sayward,C, by Theme

[, fl. 2011, two professors of logic.]

idea number gives full details    |    back to list of philosophers    |     expand these ideas
4. Formal Logic / A. Syllogistic Logic / 1. Aristotelian Logic
Syllogistic logic has one rule: what is affirmed/denied of wholes is affirmed/denied of their parts
Aristotle replace Plato's noun-verb form with unions of pairs of terms by one of four 'copulae'
The four 'perfect syllogisms' are called Barbara, Celarent, Darii and Ferio
4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
Syllogistic can't handle sentences with singular terms, or relational terms, or compound sentences
4. Formal Logic / A. Syllogistic Logic / 3. Term Logic
Term logic uses expression letters and brackets, and '-' for negative terms, and '+' for compound terms
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
In modern logic all formal validity can be characterised syntactically
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
Classical logic rests on truth and models, where constructivist logic rests on defence and refutation
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
Unlike most other signs, = cannot be eliminated
5. Theory of Logic / K. Features of Logics / 5. Incompleteness
Axioms are ω-incomplete if the instances are all derivable, but the universal quantification isn't