Abstract
The first issue concerns what can be meant by the "newness" or "originality" which Koestler attributes to the products of creative acts. One of the purposes of this paper will be to discriminate several distinct but incompatible meanings which Koestler associates with the newness in created objects. The second issue concerns whether Koestler's thesis commits him to a form of determinism or indeterminism with respect to human creative activity. The third issue raises the question whether his thesis is intended as an explanatory hypothesis or as an elaborate description of common features in creative activities. This question, of course, relates directly to the initial query about the standards of understanding which are appropriate to creative acts. And it points to the last issue which concerns the metaphysical implications of the thesis. It will be my aim to argue that a development of the metaphysics implicit in the thesis would provide a more comprehensive theory that could meet at least some of the difficulties the theory raises.