33 votes
Accepted

Is the story about Fermat's writing on a margin true?

Yes, it is true. Fermat's own copy was used in the publication of Diophantus by Fermat's son Samuel, and he included Fermat's notes. The original with Fermat's handwriting is lost. https://www.joh.cam....
Alexandre Eremenko's user avatar
18 votes
Accepted

What did Fermat do as a lawyer?

Fermat wasn't so much a "lawyer" as a magistrat which means that he sat on successively higher levels of the Parlement of Toulouse, France. This period (17th century) was before the emergence of the ...
Mikhail Katz's user avatar
  • 5,763
9 votes

What did Fermat do as a lawyer?

Read Klaus Barner's article Pierre de Fermat (1601? – 1665): His life beside mathematics (pages 12–16).
José Carlos Santos's user avatar
6 votes
Accepted

Does Fermat's Principle of Least Time imply that he believed light moved at a finite speed?

Yes, Fermat believed that the speed of light was finite, initially in reaction to the muddle created by Descartes, who wanted to have it both ways, the speed being infinite, yet different in different ...
Conifold's user avatar
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6 votes

What evidence is there that Fermat had a proof for his Last Theorem?

From the evidence that we have, it is most likely that Fermat never even claimed to have a proof of the FLT, see the extensive discussion at Mathoverflow here. Quoting from the accepted answer: Not ...
2 votes
Accepted

Fermat et l'équation de Pell

In this short article he explains the history of the solution of Pell's equation. It was proposed by Fermat in his letter to British mathematicians, and solved by Wallis and Brouncker, jointly, in ...
Alexandre Eremenko's user avatar
2 votes
Accepted

Did Kepler influence Fermat?

The question of Kepler's possible influence on Fermat is a subject of scholarly controversy, exhaustively analyzed by Cifoletti in her book on Fermat. For details see this 2018 publication in ...
Mikhail Katz's user avatar
  • 5,763

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