 As just noted, Dedekind goes beyond considering only sets of numbers in his 1888 essay. This is a significant extension of the notion of set, or of its application, an extension about which one might be concerned. An even more worrisome aspect consists of the particular way in which Dedekind’s all-encompassing totality is introduced, namely by reference to “human thought”, since this leads to the question of whether crude psychologistic features are involved (more on that topic in Section 3). But the most problematic feature—and the one Dedekind came to take seriously himself—is a third one: his set theory is subject to the set-theoretic antinomies, including Russell’s antinomy. (If any collection of objects counts as a set, then also Russell’s collection of all sets that do not contain themselves, and this leads quickly to a contradiction.) Dedekind seems to have found out about such problems from Cantor in the late 1890s (who informed him that the collection of all ordinal numbers is an “inconsistent totality”, as is the collection of all “objects of thought”). This news shocked him initially, so much that he delayed republication of Was sind und was sollen die Zahlen?; he even expressed doubts about “whether human thinking is fully rational” (Dedekind 1930–32, Vol. 3, p. 449, Dedekind 1996a, p. 836). Later he regained belief in the “inner harmony” of his approach, but without providing a solution to these problems himself (Dedekind 1930–32, Vol. 3, p. 343, Preface to the third edition, published in 1911).