The emergence of some of the nonlogical paradoxes of the theory of sets, 1903–1908

The goal of this paper is to discuss why, how, and when nonlogical set-theoretic paradoxes were discovered. No one factor dominated the whole outlook; instead, it is argued that these paradoxes were not a simple and direct consequence of the ones discovered by Bertrand Russell and published for the first time in his The Principles of Mathematics (1903).