Single Idea 4810

[catalogued under 5. Theory of Logic / K. Features of Logics / 10. Monotonicity]

Full Idea

Valid deductive arguments have the property of monotonicity; if the conclusion Q follows from the premises P, then it will also follow if further premises P* are added to P.

Gist of Idea

Valid deduction is monotonic - that is, it remains valid if further premises are added

Source

Stathis Psillos (Causation and Explanation [2002], §9.2.1)

Book Reference

Psillos,Stathis: 'Causation and Explanation' [Acumen 2002], p.248


A Reaction

For perversity's sake we could add a new premise which contradicted one of the original ones ('Socrates is a god'). Or one premise could be 'I believe..', and the new one could show that the belief was false. Induction is non-monotonic.