Alternative definition o a well order

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Can we define a well ordered set just like a totally ordered set having the least element?

Namely, is the statement "the toset T has the least element" equivalent to "any non empty subset of the toset T has the least element"?

Regards.

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No, those are not equivalent.

The non-negative reals $[0,\infty)$ with the usual ordering have a least element (namely $0$) but are not well-ordered because the subset $(1,2)$ does not contain a least element.