How To Prove It: A Structured Approach, Second Edition by Daniel J. Velleman

This is a great resource for anyone diving into mathematical logic or transitioning to higher-level math. It's the second edition of Daniel J. Velleman's classic guide, designed to help you understand and write proofs more clearly. The cover is in nice shape and the pages are clean. It's been a helpful companion for study, and it's ready for someone else to get some good use out of it. Used, but well-cared for.