  Despite the analogies, a major point of controversy is represented by Peirce’s tychism—the doctrine hinted at in the just quoted passage that ‘absolute chance’ (tyche) is of the essence of the universe. The disagreement is not as to whether there is a level of reality that escapes external determination—a striking anticipation of Heisenberg’s indeterminacy principle that both Peirce and Ward endorse. The question is as to how that most fundamental level is to be understood. In a passage that can only be interpreted as a reply to Peirce, Ward writes: