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I had a memory that the Bourbaki school proposed that $0$ be considered both positive and negative rather than neither. I cannot find any confirmation of this. Can someone point me to one or am I dreaming?

Nicolas Bourbaki (Wikipedia)

Mauro ALLEGRANZA
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badjohn
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1 Answers1

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See André Weil, Number Theory for Beginners (1979) page 2 :

A rational number is positive ($\ge 0$) or negative ($\le 0$); only $0$ is both.

Mauro ALLEGRANZA
  • 94,169
  • Thank you. I don't normally accept answers immediately but it is hard to see that a better one will come along. – badjohn Dec 01 '18 at 10:16