Page:Science and medieval thought. The Harveian oration delivered before the Royal College of Physicians, October 18, 1900 (IA sciencemedievalt00allbrich).pdf/36

30 the Nominalists; and the issues of it, in the eleventh century, at which time the "Dark Ages" passed into the earlier of the two periods of the Middle Ages, were formulated on the realist side by William of Champeaux, while the Breton Rous- selin, or Roscellinus, had the perilous honour of defining them on behalf of the nominalists. To see the depth of the difference we must step back a little, to a time when metaphysics and psychology were not distinguished from other spheres of science, and all research had for its object the nature of being. Plato himself held ideas not as mere abstractions but in some degree as creative powers; and we shall see how potent this function became in the thought of the Middle Ages when,

the universe of things is but a picture produced by the evolution of the phenomena of consciousness. The proper names for these opposite conceptions are of course Non- menalism and Phenomenalism. Realism proper as a habit of thought, whatever may have been its provisional uses, is now a mischievous habit; noumenalism is a harmless amusement.

1 Roscellinus, the Roger Bacon of the eleventh century, learned, rebellious, lucid and heroic, withstood the Church for philosophy as did Bacon in the thirteenth for natural science. It would seem that in heroism at any rate Abélard was below his master. 2 Vid. p. 50.