As I work proofs with my Calculus and Higher Geometries students, I often run across the Greek symbol that, in math, means “there exists." This might show up, for example, in statements such as “there exists” a point, a line or, (in economics) an equilibrium. Such existential issues are not foreign to mathematics, as arguably the most famous existential statement, “I think, therefore I am”, was made by Rene Descartes, who also gave us the “Cartesian Plane”, the intersection of the X and Y axes that becomes the canvas on which we draw analytic geometry.

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