The great weakness of Bergson's philosophy was that there was no place for the social in its account of consciousness. The individual and the species were the only terms; there was no account of the tribe – of the social determinations of being. When Eliot abandoned the fantasy of becoming a French poet, of dissolving his crippling American Puritanism in the brothels of Paris, he returned both to his former handwriting and to Harvard. And, in returning to Harvard, he returned not to the literature of his undergraduate degree but to its philosophy department.

Harvard philosophy had been the intellectual headquarters of Unitarianism in the early part of the nineteenth century, and it had fallen on hard times after the publication of Darwin's Origin of Species. But the legendary Harvard President Charles William Eliot (a distant cousin) had set out with spectacular success to revive the department, and, by the first decade of the twentieth century, Harvard's was the pre-eminent philosophy department in the country, and indeed had some claim to be the pre-eminent philosophy department in the world. It had also developed a distinctive American philosophy, pragmatism. Pragmatism solved the problem of realism and idealism – whether reality was to be located in the perceived world or in the mind perceiving it – by replacing these basic terms with the notion of an active community in which meaning and truth no longer found their justification in some relation between idea and reality but in the process by which a community found agreement.

The great genius of pragmatism was Charles Sanders Peirce, who understood this appeal to community as distinctively American, but, by the time Eliot began his graduate work as a philosopher, Peirce had been an isolated hermit for nearly a generation and Peirce's great friend William James, who had championed his thought at Harvard, was dead. But Josiah Royce, the third great founding father of pragmatism and the one whom Eliot was to describe as the ‘doyen of American philosophy’, was still alive, and it was Royce who was to direct Eliot 's thesis.

For Royce there were two models of a community. In the first place the community of scientists and in the second that of the early Christian Church – the congregations for whom Paul had written his epistles.