Here's one for you to ponder.
7 is a number. 7 is an integer, and integers are numbers.
7 is not a field. 7 is an element of [at least one] field, but 7 itself
is not a field.
7 is not a group. 7 is a member of the set of integers, but the set of
integers is not a group either. The set of integers form a group when
taken together with the addition operator. (And, actually, forms
another, different, group when taken with the multiplication operator.)
Now, here's the question: Is is correct to say that [3, 5, 8] is a
monad? Is it correct to say that lists are a monad? Or would it be more
correct to say that lists "form" a monad?
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