However, these assertions may be to a certain extent made not only without our objecting to them, but even with our concurrence and agreement. For in this way the wise man is represented by Epicurus as always happy. He has limited desires; he disregards death; he has a true opinion concerning the immortal Gods without any fear; he does not hesitate, if it is better for him, to depart from life. Being prepared in this manner, and armed with these principles, he is always in the enjoyment of pleasure; nor is there any period when he does not feel more pleasure than pain. For he remembers the past with gratitude, and he enjoys the present so as to notice how important and how delightful the joys which it supplies are; nor does he depend on future good, but he waits for that and enjoys the present; and is as far removed as possible from those vices which I have enumerated; and when he compares the life of fools to his own he feels great pleasure. And pain, if any does attack him, has never such power that the wise man has not more to rejoice at than to be grieved at.
But Epicurus does admirably in saying that fortune has but little power over the wise man, and that the greatest and most important events of such a man's life are managedby his own wisdom and prudence; and that greater pleasure cannot be derived from an eternity of life than such a man enjoys from this life which we see to be limited.
But in your dialectics he thought that there was no power which could contribute either to enable men to live better, or argue more conveniently. To natural philosophy he attributed a great deal of importance. For by the one science it is only the meaning of words and the character of a speech, and the way in which arguments follow from or are inconsistent with one another, that can be seen; but if the nature of all things is known, we are by that knowledge relieved from superstition, released from the fear of death, exempted from being perplexed by our ignorance of things, from which ignorance horrible fears often arise. Lastly, we shall be improved in our morals when we have learnt what nature requires. Moreover, if we have an accurate knowledge of things, preserving that rule which has fallen from heaven as it were for the knowledge of all things, by which all our judgments of things are to be regulated, we shall never abandon our opinions because of being overcome by any one's eloquence.
For unless the nature of things is thoroughly known, we shall have no means by which we can defend the judgments formed by our senses. Moreover, whatever we discern by our intellect, all arises from the senses. And if our senses are all correct, as the theory of Epicurus affirms, then something may be discerned and understood accurately; but as to those men who deny the power of the senses, and say that nothing can be known by them, those very men, if the senses are discarded, will be unable to explain that very point which they are arguing about. Besides, if all knowledge and science is put out of the question, then there is an end also of all settled principles of living and of doing anything.
Thus, by means of natural philosophy, courage is desired to withstand the fear of death, and constancy to put aside the claims engendered by superstition; and by removing ignorance of all secret things, tranquillity of mind is produced; and by explaining the nature of desires and their different kinds, we get moderation: and (as I just now explained) by means of this rule of knowledge, and of the judgment which is established and corrected by it, the power of distinguishing truth from falsehood is put into man's hands.