Cardinality is exactly a measurement unit of the size (or magnitude) of existence.
"In mathematics, the cardinality of a set is a measure of the "number of elements of the set". For example, the set A = {2, 4, 6} contains 3 elements, and therefore A has a cardinality of 3."
"Really? I didn't know that. So like {G, o, d} = 3?"