which constitutes your being, but your mind; not that substance which is palpable to the senses, but your spiritual nature. Know, then, that you are a God—for a God it must be, which flourishes, and feels, and recollects, and foresees, and governs, regulates and moves the body over which it is set, as the Supreme Ruler does the world which is subject to him. For as that Eternal Being moves whatever is mortal in this world, so the immortal mind of man moves the frail body with which it is connected.
XXV. For whatever is always moving must be eternal; but that which derives its motion from a power which is foreign to itself, when that motion ceases must itself lose its animation.
That alone, then, which moves itself can never cease to be moved, because it can never desert itself. Moreover, it must be the source, and origin, and principle of motion in all the rest. There can be nothing prior to a principle, for all things must originate from it; and it cannot itself derive its existence from any other source, for if it did it would no longer be a principle. And if it had no beginning, it can have no end; for a beginning that is put an end to will neither be renewed by any other cause, nor will it produce anything else of itself. All things, therefore, must originate from one source. Thus it follows that motion must have its source in something which is moved by itself, and which can neither have a beginning nor an end. Otherwise all the heavens and all nature must perish, for it is impossible that they can of themselves acquire any power of producing motion in themselves.
XXVI. As, therefore, it is plain that what is moved by itself must be eternal, who will deny that this is the general condition and nature of minds? For as everything is inanimate which is moved by an impulse exterior to itself, so what is animated is moved by an interior impulse of its own; for this is the peculiar nature and power of mind. And if that alone has the power of self-motion, it can neither have had a beginning, nor can it have an end.
Do you, therefore, exercise this mind of yours in the best pursuits. And the best pursuits are those which consist in promoting the good of your country. Such employments will speed the flight of your mind to this its
