Then when I say, "Sound intellect reproves their words As false, and turns away," I conclude this error to be confuted, and I say that it is time to open the eyes to the Truth; and this is expressed when I say, "And now I seek to tell, As it appears to me." It is now evident to sound minds that the words of those men are vain, that is, without a crumb or particle of Truth; and I say sound not without cause. Our intellect may be said to be sound or unsound. And I say intellect for the noble part of our Soul, which it is possible to designate by the common word "Mind." It may be called sound or healthy, when it is not obstructed in its action by sickness of mind or body, which is to know what things are, as Aristotle expresses it in the third chapter on the Soul. For, owing to the sickness of the Soul, I have seen three horrible infirmities in the minds of men. One is caused by natural vanity, for many men are so presumptuous that they believe they know everything, and, owing to this, they assert things to be facts which are not facts. Tullius especially execrates this vice in the first chapter of the Offices, and St. Thomas in his book against the Gentiles, saying: "There are many men, so presumptuous in their conceit, who believe that they can compass all things with their intellect, deeming all that appears to them to be true, and count as false that which does not appear to them." Hence it arises that they never attain to any knowledge; believing themselves to be sufficiently learned, they never inquire, they never listen; they desire to be inquired of, and when a question is put, bad enough is their reply. Of those men Solomon speaks in Proverbs: "Seest thou a man that is hasty in his words? there is more hope of a fool than of him." Another infirmity of mind is caused by natural weakness or smallness, for many men are so vilely obstinate or stubborn that they cannot believe that it is possible either for them or for others to know things; and such men as these never of themselves seek knowledge, nor ever reason; for what other men say, they care not at all. And against these men Aristotle speaks in the first book of the Ethics, declaring those men to be insufficient or unsatisfactory hearers of Moral Philosophy. Those men always live, like beasts, a life of grossness, the despair of all learning.