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4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic

[general ideas about formal arguments in syllogism form]

14 ideas
Aristotle's said some Fs are G or some Fs are not G, forgetting that there might be no Fs [Bostock on Aristotle]
Stoics like syllogisms, for showing what is demonstrative, which corrects opinions [Stoic school, by Diog. Laertius]
Syllogisms are verbal fencing, not discovery [Locke]
Many people can reason well, yet can't make a syllogism [Locke]
Frege thought traditional categories had psychological and linguistic impurities [Frege]
The Darapti syllogism is fallacious: All M is S, all M is P, so some S is P' - but if there is no M? [Russell]
The mortality of Socrates is more certain from induction than it is from deduction [Russell]
The universal syllogism is now expressed as the transitivity of subclasses [Putnam]
The Square of Opposition has two contradictory pairs, one contrary pair, and one sub-contrary pair [Harré]
Venn Diagrams map three predicates into eight compartments, then look for the conclusion [Bostock]
An 'enthymeme' is an argument with an indispensable unstated assumption [Yablo]
'No councillors are bankers' and 'All bankers are athletes' implies 'Some athletes are not councillors' [Devlin]
'Equivocation' is when terms do not mean the same thing in premises and conclusion [Beall/Restall]
Syllogistic can't handle sentences with singular terms, or relational terms, or compound sentences [Engelbretsen/Sayward]