Analysis of Rules of Inference and Rules of Replacement

Two students hand in the same conclusion. One reaches it by guessing. The other reaches it by naming, at every step, exactly which of nineteen rules let them take that step. Only the second answer gets full marks — because this topic is not about getting the right answer, it is about proving you got there legitimately.

In two minutes

Rules of Inference let you draw a new line from lines you already have; Rules of Replacement let you swap one formula for a logically identical one — together, nineteen tools, and every PYQ here is really just asking which one you used.

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.