Seth Warner > Quotes

“For example, if P is the set of presidents of the United States before 1900, then Hayes ∈ P, Tilden P, 17 P. If H is the set of all heads of state in 1863 together with the number 1863, then Lincoln ∈ H, Wilson H, Victoria ∈ H, 1776 H, Napoleon III ∈ H, 1863 ∈ H.”
― Seth Warner, Modern Algebra