Figures and Moods — Testing the validity of arguments

Shuffle the same three ingredients — two premises and a conclusion — and you can build hundreds of different-looking syllogisms. Only a small number of them are actually valid. This topic gives you the two coordinates that locate any syllogism on that map — its figure and its mood — and a mechanical test that tells you, for any syllogism at all, whether it survives.

In two minutes

A syllogism's figure is fixed by where its middle term sits in the two premises, its mood is fixed by the quality and quantity of its three propositions, and only a handful of the sixty-four possible mood combinations are valid in each figure.

The rest of this chapter

The full explanation, the cheat sheet, every previous-year question at every mark weight, the quiz and the answer skeletons are part of Logic – II on LexBlox Semester. Sign in to unlock the subject, or read Module 1 of Legal Language and Writing free.