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Could someone please tell me what are the initial and final objects in the category of sets and topological spaces? I had been very confused by this question. Thanks!

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I should have looked here first! Thank you! – Ben V Jul 14 '14 at 16:44
up vote 2 down vote accepted

In many concrete categories, the initial object is either the empty object, or some similar thing like the free object on no generators.

In many concrete categories, the terminal object is the one-point set.

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I think it should be "in many $\textit {interesting} $ concrete categories". Otherwise, your claim is just not true. – Jakob Werner Jul 14 '14 at 4:42

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