Description: The first infinite cardinal number, discovered by Georg Cantor in 1873,
has the same size as the set of natural numbers _om (and under our
particular definition is also equal to it). In the literature, the
argument of the aleph function is often written as a subscript, and the
first aleph is written aleph_0. Exercise 3 of TakeutiZaring p. 91.
Also Definition 12(i) of Suppes p. 228. From Moshé Machover,Set
Theory, Logic, and Their Limitations, p. 95: "Aleph ... the first letter
in the Hebrew alphabet ... is also the first letter of the Hebrew word ...
(_einsoph_, meaning infinity), which is a cabbalistic appellation of the
deity. The notation is due to Cantor, who was deeply interested in
mysticism." (Contributed by NM, 21-Oct-2003)(Revised by Mario
Carneiro, 13-Sep-2013)