more from Stephen Read

Single Idea 14188

[catalogued under 5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence]

Full Idea

Belief that every valid argument is valid in virtue of form is a myth. ..Validity is a question of the impossibility of true premises and false conclusion for whatever reason, and some arguments are materially valid and the reason is not purely logical.

Gist of Idea

Not all arguments are valid because of form; validity is just true premises and false conclusion being impossible


Stephen Read (Formal and Material Consequence [1994], 'Logic')

Book Reference

'Philosophy of Logic: an anthology', ed/tr. Jacquette,Dale [Blackwell 2002], p.245

A Reaction

An example of a non-logical reason is the transitive nature of 'taller than'. Conceptual connections are the usual example, as in 'it's red so it is coloured'. This seems to be a defence of the priority of semantic consequence in logic.

Related Idea

Idea 14182 If the logic of 'taller of' rests just on meaning, then logic may be the study of merely formal consequence [Read]