The same honour is also attributed to natural philosophy, and not without reason, because the man who wishes to live in a manner suitable to nature, must begin by studying the universal world, and the laws which govern it. Nor can any one form a correct judgment of good and evil without being acquainted with the whole system of nature, and of the life of the gods also, and without knowing whether or not the nature of man agrees with universal nature. He must also have learnt the ancient rules of those wise men who bid men yield to the times, and obey God, and know oneself, and shun every kind of excess. Now, without a knowledge of natural philosophy, no man can see what great power these rules have; and it is as great as can be: and also this is the only knowledge which can teach a man how greatly nature assists in the cultivation of justice, in the maintenance of friendship and the rest of the affections. Nor can piety towards the Gods, nor the gratitude which is due to them, be properly understood and appreciated without a correct understanding of the laws of nature.
But I feel now that I have advanced further than I had intended, or than the subject before me required. But the admirable arrangement of the Stoic doctrine, and the incredible beauty of the system, drew me on. And, in the name of the immortal gods! can you forbear to admire it? For what is there in all nature—though nothing is better or more accurately adapted to its ends than that—or what can be found in any work made by the hand, so well arranged, and united, and put together? What is there which is posterior, which does not agree with what has preceded it? What is therewhich follows, and does not correspond to what has gone before? What is there which is not connected with something else in such a manner, that if you only move one letter the whole will fall to pieces? Nor, indeed, is there anything which can be moved.
But what a grand and magnificent and consistent character is that of the wise man which is drawn by them! For he, after reason has taught him that that which is honourable is alone good, must inevitably be always happy, and must have a genuine right to those names which are often ridiculed by the ignorant. For he will be more properly called king than Tarquin, who was able to govern neither himself nor his family; he will deserve to be called the master of the people more than Sylla, who was only the master of three pestiferous vices, luxury, avarice, and cruelty; he will be called rich more properly than Crassus, who would never have desired to cross the Euphrates without any legitimate cause for war, if he had not been in want of something. Everything will be properly said to belong to that man, who alone knows how to make use of everything. He will also rightly be called beautiful, for the features of the mind are more beautiful than those of the body: he will deservedly be called the only free man, who is neither subject to the domination of any one, nor subservient to his own passions. He will fairly be called invincible, on whose mind, even though his body be bound with chains, no fetters can ever be imposed. Nor will he wait till the last period of his life, so as to have it decided whether he has been happy or not, after he has come to the last day of life and closed his eyes in death, in the spirit of the warning which one of the wise men gave to Crœsus, without showing much wisdom in so doing. For if he had ever been happy, then he would have borne his happy life with him, even as far as the funeral pile built for him by Cyrus.
But if it be true that no one except a good man is happy, and that all good men are happy, then what deserves to be cultivated more than philosophy, or what is more divine than virtue?