User:Thehalfone

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If S is an infinite definable set of some structure (mathematical logic) and A:=\{a_1,a_2,\ldots,a_n\} is any finite subset, then A is definable via the formula (mathematical logic) x=a_1 \lor x=a_2 \lor \ldots \lor x=a_n.

Similarly, any subset of S which is cofinite, that is whose compliment is finite, is definable.

S is said to be minimal iff these are the only definable subsets of S.

A structure is said to be minimal iff its domain is a minimal set.

See also

  • Strong minimality