 Both epistemological and ontological idealism came under massive attack in Britain at the turn of the twentieth century by George Edward Moore (1873–1958) and Bertrand Russell (1872–1970), while in the United States Royce’s position was attacked by a school of younger “New Realists”, to some extent inspired by his life-long interlocutor William James, who included E.B. Holt and his younger Harvard colleague Ralph Barton Perry, and later Roy Wood Sellars (the father of Wilfrid Sellars, who later moved back to a form of Kantianism), and Arthur Lovejoy. Both Moore and Russell had more of an enduring influence on the course of analytic philosophy than did the American New Realists, but also reveal the continuing impulse to idealism in spite of their own efforts, so we will focus on them. Both of them take idealism to be spiritualism in the spirit of Berkeley and Bradley (neither of them mentions their own Cambridge tutor McTaggart!), i.e., they think of idealism as a position characterized by the claim that the universe (Moore) or whatever exists or whatever can be known to exist (Russell) is spiritual (Moore) or in some sense mental (Russell). Although their attack was so influential that even more than a hundred years later, any acknowledgment of idealistic tendencies is viewed in the English-speaking world with reservation, it is by no means obvious that they actually thought they had disproved idealism. On the contrary, neither Moore nor Russell claimed to have demonstrated that the universe or what exists or can be known to exist is not spiritual or mental. All that they take themselves to have shown is that there are no good philosophical (in contradistinction to, e.g., theological or psychological) arguments available to support such a claim. Moore especially is very explicit about this point. He devotes the first five pages of his famous piece from 1903, “The Refutation of Idealism”, to assuring the reader over and over that