"We must subscribe to the requirements of Nature. That's Nature with a capital N."

Physics is fundamental to Stoicism. These demonstrations of some properties of rolling matter are referenced in our book, "On Virtue," in its discussion of the motion of the life in a person, which we call emotion, as well as in its discussion of Temperance. One of Nature's requirements is that the properties of physics enable us to understand the properties of greater realities which we cannot observe with our five senses, such as life, thought, and reason.