[219] Do thou then, O my soul, travel through the land, and through man, bringing if you think fit, each individual man to a judgment of the things which concern him; as, for instance, what the body is, and under what influences, whether active or passive, it co-operates with the mind; what the external sense is, and in what manner that assists the dominant mind; what speech is, and of what it becomes the interpreter so as to contribute to virtue; what are pleasure and desire; what are pain and fear; and what art is capable of supplying a remedy for these things; by the aid of which a man when infected with these feelings may easily escape, or else perhaps may never be infected at all: what folly is, what intemperance, what committing injustice, what the whole multitude of other diseases, which it is the nature of all destructive vice to engender; and also what are the means by which they can be averted. And also, on the contrary, what justice is, what prudence is, and temperance, and manly courage, and deliberate wisdom, and in short what each virtue is, and what the mastery over the passions is, and in what way each of these virtues is usually produced.