Book 5, Chapter 24

68 “But rather than merely touch in words on what we wish to demonstrate, we must set before ourselves something like living pictures, which will draw us more powerfully toward knowledge and understanding. Let us take a man distinguished by the finest accomplishments, and for a moment form his image in our minds. First, he must possess exceptional intelligence, for virtue does not readily accompany sluggish minds; next, an ardent passion for investigating the truth. From this will spring that threefold fruit of the mind: first, knowledge of reality and the explanation of nature; second, the discrimination of things to be sought and avoided, and the principles of living well; third, the judgment of what follows from any proposition and what contradicts it, which embraces both precision in argument and truth in judgment.

69 “What joy, then, must fill the wise man’s mind as it lives with these pursuits, spending its very nights with them! Think of his discerning the motions and revolutions of the entire universe: seeing the countless stars fixed in the heavens, keeping pace with the motion of the sky itself, each fastened in its appointed place; seeing seven others each follow its own course, widely separated from one another in their heights or depths, their wandering motions nevertheless marking out fixed and certain intervals in their paths. Surely it was the sight of these things that stirred the ancients and urged them to inquire further. From this arose the search for the first principles, the seeds, as it were, from which all things sprang, were generated, and took form: the origin of each kind, inanimate or living, voiceless or speaking; its life and its end; the succession and transformation of one thing into another; the source of the earth and the weights that balance it; the hollows in which the seas are held; the force of gravity that carries everything down to seek the center of the universe, which in a sphere is also its lowest point.”

68 “But let’s not just touch on what we’re trying to show in words. We need to put some pictures in motion, so to speak, to draw us more directly toward knowing and understanding it. Let’s take a man who excels in the finest pursuits and picture him in our minds for a moment. First, he must have outstanding natural ability. Virtue doesn’t easily go along with a slow mind. Next, he must have an eager drive to discover the truth. This will produce those three kinds of mental achievement. One consists in knowing things and explaining nature. Another sets out what to pursue and what to avoid, and how to live well. The third determines what follows from each thing and what conflicts with it. This last contains both the whole subtle art of argument and sound judgment about the truth.

69 “What joy must fill a wise person’s mind when these are the interests he lives with, day and night! He’ll have understood the movements and revolutions of the whole universe. He’ll have seen countless stars attached to the sky, fixed in particular places and moving along with the sky itself. Seven others each follow their own paths, at very different heights and depths. Wandering as their movements seem, they mark out regular, fixed stretches of their own courses. The sight of these surely gave those early thinkers the impulse and the hint to ask further questions. This led to the search for beginnings, for the seeds, so to speak, from which everything arose, was generated, and took shape. They asked about the origin, life, and destruction of each kind of thing, lifeless or living, speechless or speaking, and how one thing turns and changes into another. They asked where the earth came from, what weights hold it in balance, and what hollows support the seas. What force of weight pulls everything down toward the center of the universe, always its destination, which in a sphere is also the lowest point?”