18.090 Introduction To Mathematical Reasoning Mit __full__ May 2026

Course Report: MIT 18.090 Introduction to Mathematical Reasoning

The course curriculum is a blend of fundamental logic and introductory concepts from higher-level mathematics: 18.0x - MIT Mathematics 18.090 introduction to mathematical reasoning mit

• Note: This is often the "sister" course to 18.090. It covers Induction, Graph Theory, and Relations very thoroughly.

Who Should Take This Course?

The Problem Sets (P-Sets)

P-sets are released weekly and typically contain 6–8 problems. The first problem is usually a "warm-up" (build a truth table). The last problem is a "challenge" (a non-trivial proof from number theory or combinatorics). MIT students report spending 6–10 hours per week on the 18.090 p-set alone. The key rule: No collaboration on the final two problems. You must stand alone with your reasoning. Course Report: MIT 18

• "Theorem Proving in Lean 4" (free online, by Avigad, de Moura, et al.) – Chapters 1–4 cover propositional logic and quantifiers exactly as taught in 18.090.

Many math and computer science majors take both 18.090 and 6.042, noting that 18.090 offers a purer, theorem-proving experience. Note: This is often the "sister" course to 18