During the Victorian era, British pure mathematicians tried to fashion for themselves a plausible justification for indulging in pure, rather than applied, mathematics. Professionalisation does not supply an explanation for pure mathematicians’ ultimate success, for the relevant criteria were not met. The claim that they were providing a store of methods and results for future use in the applied sciences had already run out of steam by the 1850s, due to the quantity of pure mathematics that was being produced, and the implicit denial of pure mathematicians’ true motives. The portrayal of the pure mathematician in the same light as the natural historian, exploring and reporting on the immaterial but real world of mathematics, left unanswered questions concerning the value of this activity for society. Moreover, the suggestion that vigorous pure mathematical activity was necessary for the advancement of humankind was no argument at all, but merely an assertion backed up by misstated facts. Accordingly, by the late 1870s it was clear that for pure mathematicians to have any credibility in the eyes of the world-at-large, they needed to present their discipline in a completely new way.