Fermat Claimed His Proof Would Not Fit in the Margin
A margin is an edge or a difference. Mathematics owes one of its most famous notes to a book margin.
A margin is the edge of something, or the difference between two amounts. The most famous margin in history belonged to Pierre de Fermat, who wrote in his copy of Diophantus around 1637 that he had a marvellous proof of a theorem which the margin was too narrow to contain. It took mathematicians until 1994 to find one.
- An edge. *The margin of the page.*
- A difference. *A narrow margin.*
- Profit above cost. *A thin margin.*
- Marginal — at the edge, or slight. *A marginal improvement.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun | margin | A wide margin. |
| Plural | margins | Tight margins. |
| Adjective | marginal | A marginal seat. |
| Verb | marginalise | Marginalised groups. |
| Related | marginalia | Handwritten marginalia. |
How it is used in a sentence
- He won by a narrow margin.Difference.
- A marginal seat can change hands.Politics.
- Marginalia are notes in the margin.Sometimes more interesting than the book.
Margin in different fields
- Publishing — the blank border of a page
- Business — the difference between cost and selling price
- Politics — a marginal seat, won by a small number of votes
- Finance — margin trading, borrowing to invest
- Economics — marginal cost, the cost of producing one more unit
From Latin *margo*, an edge or border — related to English *mark* and to the *march* meaning a border territory.
Was Fermat's proof ever found?
His was not. Andrew Wiles proved the theorem in 1994 using mathematics developed centuries after Fermat's death.
Are margin and march related?
Yes. A march in the sense of a border region, as in the Welsh Marches, comes from the same root meaning edge.