Aleph one

Aleph one, written as ${\displaystyle \aleph _{1}}$, is an infinite cardinal number following aleph null (${\displaystyle \aleph _{0}}$).^[1] It is the cardinality (size) of the set of numbers of possible arrangements for all countably infinite sets. Under the continuum hypothesis, it is also the cardinality of the real numbers.^[2] Aleph one is followed by aleph two, ${\displaystyle \aleph _{2}}$, even with an infinite amount of time you could simply never list every single element or number in any uncountable set.

Related pages

• Infinity
• Uncountable set