Is it possible to extend the set-inclusion order of a power set to a well-ordering?

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The original aim is to define recursively a function on the power set of a set such that the functional value of a subset is determined by those of its proper subsets.

Thank you.

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If the set if finite, yes; every linear extension of the set-inclusion order is a well-ordering.

If the set is infinite, no; there is a strictly decreasing infinite sequence of subsets.

A partial order can be extended to a well-ordering if and only if it is well-founded, meaning that it has no strictly decreasing infinite sequence.