Don Diego; "all I can tell thee is that I have seen him act the acts of the greatest madman in the world, and heard him make observations so sensible that they efface and undo all he does; do thou talk to him and feel the pulse of his wits, and as thou art shrewd, form the most reasonable conclusion thou canst as to his wisdom or folly; though, to tell the truth, I am more inclined to take him to be mad than sane." With this Don Lorenzo went away to entertain Don Quixote as has been said, and in the course of the conversation that passed between them Don Quixote said to Don Lorenzo, "Your father, Senor Don Diego de Miranda, has told me of the rare abilities and subtle intellect you possess, and, above all, that you are a great poet." "A poet, it may be," replied Don Lorenzo, "but a great one, by no means.
It is true that I am somewhat given to poetry and to reading good poets, but not so much so as to justify the title of 'great' which my father gives me." "I do not dislike that modesty," said Don Quixote; "for there is no poet who is not conceited and does not think he is the best poet in the world." "There is no rule without an exception," said Don Lorenzo; "there may be some who are poets and yet do not think they are." "Very few," said Don Quixote; "but tell me, what verses are those which you have now in hand, and which your father tells me keep you somewhat restless and absorbed?
If it be some gloss, I know something about glosses, and I should like to hear them; and if they are for a poetical tournament, contrive to carry off the second prize; for the first always goes by favour or personal standing, the second by simple justice; and so the third comes to be the second, and the first, reckoning in this way, will be third, in the same way as licentiate degrees are conferred at the universities; but, for all that, the title of first is a great distinction." "So far," said Don Lorenzo to himself, "I should not take you to be a madman; but let us go on." So he said to him, "Your worship has apparently attended the schools; what sciences have you studied ?" "That of knight-errantry," said Don Quixote, "which is as good as that of poetry, and even a finger or two above it." "I do not know what science that is," said Don Lorenzo, "and until now I have never heard of it." "It is a science," said Don Quixote, "that comprehends in itself all or most of the sciences in the world, for he who professes it must be a jurist, and must know the rules of justice, distributive and equitable, so as to give to each one what belongs to him and is due to him.

He must be a theologian, so as to be able to give a clear and distinctive reason for the Christian faith he professes, wherever it may be asked of him.

He must be a physician, and above all a herbalist, so as in wastes and solitudes to know the herbs that have the property of healing wounds, for a knight-errant must not go looking for some one to cure him at every step.

He must be an astronomer, so as to know by the stars how many hours of the night have passed, and what clime and quarter of the world he is in.

He must know mathematics, for at every turn some occasion for them will present itself to him; and, putting it aside that he must be adorned with all the virtues, cardinal and theological, to come down to minor particulars, he must, I say, be able to swim as well as Nicholas or Nicolao the Fish could, as the story goes; he must know how to shoe a horse, and repair his saddle and bridle; and, to return to higher matters, he must be faithful to God and to his lady; he must be pure in thought, decorous in words, generous in works, valiant in deeds, patient in suffering, compassionate towards the needy, and, lastly, an upholder of the truth though its defence should cost him his life.