Syllogism — Rules and Fallacies

Someone on a Mumbai local says: “All good lawyers argue well. My cousin argues well. So my cousin must be a good lawyer.” It sounds fine until you notice that “argues well” is doing two different jobs in two different sentences. That single slip is a categorical syllogism breaking a rule — and this topic is the full list of rules it can break, with a name for each break.

In two minutes

A categorical syllogism is a three-term, three-proposition deductive argument, and it is valid only if it obeys eight rules; break any one and the argument commits a named fallacy.

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.