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Closed 6 years ago.
I tried to search the defintion of ϵ, but only got that it is the fifth letter in the Greek alphabet.
I want to know why it was chosen the way it was?
This is something not very obvious, unlike the symbol ∈, which means element of. That makes sense because ∈ looks like an E which can stand for element.
But epsilon is just an alphabet letter, and so why was it chosen?
