While the Eleatics exclaimed all is, Heraclitus rejoined that it is truer to say all is not—not meaning, of course, that there is absolutely no universe, but intimating that the universe is not a definite and completed and unchanging existence, but is an ever-varying process, and that in considering the on-goings of nature the negative moment, the moment of disappearance, the moment in which each change vanished, in short, the moment of not-Being, was fully as important as the positive moment, the moment of appearance, the moment in which each change arose, in short, the moment of Being.
21. Being, then, and not-Being are, according to Heraclitus, the elements or moments of Becoming. To understand this, just consider once more what is meant by Becoming. By a process or a becoming is meant continual change, not change by what we may call leaps and starts. In natura nihil fit per saltum; In nature nothing is ever done by a jump. Nature changes not by jerks, but smoothly and continuously. The changing states are so continuous, so finely graduated into each other, so infinitely minute, that each of them passes away in the very instant in which it is. Each of them, in the very act of being, is merged in its successor. Now here we are compelled to say that each of these states is. This our reason necessitates; but then, inasmuch as each state is not stationary, but is ended as soon as it is begun, we are equally compelled by our reason to
