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Old 26-08-2011, 11:17 AM posted to sci.lang,alt.usage.english,,sci.math
pauljk pauljk is offline
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Default doughnut, coffee cup, scissors, pretzel, ...

"Peter Moylan" wrote in message
. au...
Jonathan de Boyne Pollard wrote:
That might explain it, I guess. So if I see something before me that I
am inclined to refer to as a "coffee cup", how am I to tell whether or
not it actually _is_ a coffee cup in some essential way?

In fact, it could be your doughnut.

(Old topology joke.)

My doughnuts are generally not continuously deformable to coffee cups.
I'd have to poke them with a stick to make that true, and that would
squirt jam everywhere.

Would topology have still been the field it is today if doughnuts had
not existed?

All topology textbooks would contain pictures of coffee cups.

Or topologically identical people?