 In what follows, we will concentrate mainly on the discussion of philosophical theories that either endorse or claim to endorse idealism on ontological and/or epistemological grounds. At some points in its complex history, however, above all in the social as well as philosophical movement that dominated British and American universities in the second half of the nineteenth century and through the first World War, idealism in either of its philosophical forms was indeed connected to idealism in the popular sense of progressive and optimistic social thought. This was true for figures such as Bradley and Royce and their predecessors and contemporaries such as Thomas Hill Green and Bernard Bosanquet. There has recently been considerable interest in British or more generally Anglophone idealism as a movement in social philosophy, or even a social movement, but we will not pursue that here (see Mander 2011; Boucher &amp; Vincent 2012; Mander [ed.] 2000; and Mander &amp; Panagakou [eds.] 2016).