Love of Logic [Science Tattoo]

Melissa writes,

 

I have a mathematical tattoo on my left forearm. It’s in Frege’s notation (from “Grundgesetze der Arithmetik”), which was one of the first modern logical notations. If it were written on a flat surface, it would start with the short vertical line, which is the assertion sign. What it asserts is: If {Cantor’s theorem} then {heart}.

Cantor’s Theorem says that the power set of any set is strictly larger than the set itself. (The power set of a set is the set of all its subsets.) For finite sets, this is pretty obvious; for example, the power set of {1,2} is {{}, {1}, {2}, {1,2}}. In general, if a finite set has n members, its power set has 2^n. But

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