 The second famous published antinomy (Russell 1903, paragraphs 78, 101–106; Frege 1903, Appendix, dated October 1902; see the entry  Russell’s paradox  and Klement 2010) takes us from Cantor’s paradise into the realm of the foundations of logic and the philosophy of mathematics. It is strikingly simple, involves only predicate application, and it has an explicit self-referential (reflexive) character. In Russell’s own words (June 16, 1902, letter to Frege, translation in van Heijenoort 1963, pp. 124–125),