Mathematics — Methods & Tools

Mathematics
Methods and Tools
How mathematicians work: proof, conjecture, theorem. Fermat’s Last Theorem as a case study.
Published

March 5, 2026

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Notes

Case study: Fermat’s Last Theorem

\[\forall\, n \in \mathbb{Z},\ n>2,\ \nexists\, a,b,c \in \mathbb{Z}_{>0} \text{ such that } a^n + b^n = c^n\]

Stated by Fermat in 1637. Proved by Andrew Wiles in 1995. The key TOK questions:

  • What is the difference between a and a ?
  • How do mathematicians establish ?
  • Does mathematics use empirical testing? (No — you cannot prove a theorem by checking examples.)
  • Is there creativity in mathematics? Does emotion play a role? (Wiles wept when he found the gap in his proof.)
  • Is a that is “mostly right” still a proof? (No — one error invalidates the whole argument.)