more from this thinker     |     more from this text


Single Idea 18806

[filed under theme 4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic ]

Full Idea

Frege rejected the traditional categories as importing psychological and linguistic impurities into logic.

Gist of Idea

Frege thought traditional categories had psychological and linguistic impurities

Source

report of Gottlob Frege (Function and Concept [1891]) by Ian Rumfitt - The Boundary Stones of Thought 1.2

Book Ref

Rumfitt,Ian: 'The Boundary Stones of Thought' [OUP 2015], p.18


A Reaction

Resisting such impurities is the main motivation for making logic entirely symbolic, but it doesn't follow that the traditional categories have to be dropped.


The 14 ideas with the same theme [general ideas about formal arguments in syllogism form]:

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, by Rumfitt]
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]