All things are in flux; the flux is subject to a unifying measure or rational principle. This principle (logos, the hidden harmony behind all change) bound opposites together in a unified tension, which is like that of a lyre, where a stable harmonious sound emerges from the tension of the opposing forces that arise from the bow bound together by the string.
HeraclitusThe river where you set your foot just now is gone-those waters give way to this, now this.
HeraclitusEven what those with the greatest reputation for knowing it all claim to understand and defend are but opinions.
Heraclitus