Why is Negative times Positive Negative? (TANTON Mathematics) @DrJamesTanton

Uploaded March 2010 | Updated September 2026, 3 weeks ago

This is a subtle question!

In this video I make clear which piece of mathematics we choose to accept (and it is a choice!) that makes numbers behave this way. If you choose not to make this choice, that's fine! You'll have created for yourself a new type of mathematics.

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