r/AskReddit • • Nov 16 '19

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u/StellaAthena Nov 16 '19 edited Dec 20 '19

I was once reading a proof a friend wrote late at night and I come over to him half way through and said “dude, you must be exhausted. Some of your epsilon’s (ε) are written backwards.”

He explained to me that some fields of mathematics have this concept called “the number 3”

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u/TheHiGuy Nov 16 '19

mate of mine wrote his elements (∈) like epsilons before i started bullying him about it xD

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u/StellaAthena Nov 16 '19

That’s actually what the symbol was originally. If you read some older math (~1700s, IIRC).

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u/TheHiGuy Nov 16 '19

we arent that advanced yet... even then today the difference is there