 Such generalized notions of set and function, together with the acceptance of the actual infinite, were soon attacked by finitistically and constructively oriented mathematicians like Kronecker. Dedekind defended his approach by pointing to its fruitfulness (Dedekind 1888a, first footnote, cf. Edwards 1983, Ferreirós 1999, ch. 7). But eventually he came to see one feature of it as problematic: his implicit acceptance of a general comprehension principle (another sense in which his notion of set is unrestricted). We already touched on a specific way in which this comes up in Dedekind’s work. Namely, in Was sind und was sollen die Zahlen? he introduces “the totality of all things that can be objects of my thought” (his “universal set”), together with arbitrary subsets of that totality (a general Aussonderungsaxiom is used). But then, any collection of objects counts as a set.