Another circumstance that invites a restatement of rational ethics is the impressive illustration of their principle which subsequent history has afforded. Mankind has been making extraordinary experiments of which Aristotle could not dream; and their result is calculated to clarify even his philosophy. For in some respects it needed experiments and clarification. He had been led into a systematic fusion of dialectic with physics, and of this fusion all pretentious modern philosophy is the aggravated extension. Socrates’ pupils could not abandon his ideal principles, yet they could not bear to abstain from physics altogether; they therefore made a mock physics in moral terms, out of which theology was afterward developed. Plato, standing nearer to Socrates and being no naturalist by disposition, never carried the fatal experiment beyond the mythical stage. He accordingly remained the purer moralist, much as Aristotle’s judgment may be preferred in many particulars. Their relative position may be roughly indicated by saying that Plato had no physics and that Aristotle’s physics was false; so that ideal science in the one suffered from want of environment and control, while in the other it suffered from misuse in a sphere where it had no application. [Sidenote: Plato’s myths in lieu of physics.] What had happened was briefly this: Plato, having studied many sorts of philosophy and being a bold and universal genius, was not satisfied to leave all physical questions pending, as his master had done. He adopted, accordingly, Heraclitus’s doctrine of the immediate, which he now called the realm of phenomena; for what exists at any instant, if you arrest and name it, turns out to have been an embodiment of some logical essence, such as discourse might define; in every fact some idea makes its appearance, and such an apparition of the ideal is a phenomenon. Moreover, another philosophy had made a deep impression on Plato’s mind and had helped to develop Socratic definitions: Parmenides had called the concept of pure Being the only reality; and to satisfy the strong dialectic by which this doctrine was supported and at the same time to bridge the infinite chasm between one formless substance and many appearances irrelevant to it, Plato substituted the many Socratic ideas, all of which were relevant to appearance, for the one concept of Parmenides. The ideas thus acquired what is called metaphysical subsistence; for they stood in the place of the Eleatic Absolute, and at the same time were the realities that phenomena manifested.