It is impossible to square the circle perfectly because of its arc.

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In the third chapter of this book, a promise was made to discuss the loftiness of the imperial and philosophic authorities. Therefore having discussed the imperial authority, I must continue my digression and take up the subject of the authority of the Philosopher, in keeping with my promise. Here we must first observe what this word "authority" means, for there is a greater necessity to know this in discussing the philosophic as opposed to the imperial authority, which by virtue of its majesty does not seem open to question. It should be known, then, that "authority" is nothing but "the pronouncement of an author."

This word, namely "auctor" without the third letter c, has two possible sources of derivation. One is a verb that has very much fallen out of use in Latin and which signifies more or less "to tie words together," that is, "auieo." Anyone who studies it carefully in its first form will observe that it displays its own meaning, for it is made up only of the ties of words, that is, of the five vowels alone, which are the soul and tie of every word, and is composed of them in a different order, so as to portray the image of a tie. For beginning with A it turns back to U, goes straight through to I and E, then turns back and comes to O, so that it truly portrays this image: A, E, I, O, U, which is the figure of a tie. Insofar as "author" is derived and comes from this verb, it is used only to refer to poets who have tied their words together with the art of poetry; but at present we are not concerned with this meaning. The other source from which "author" derives, as Uguccione attests in the beginning of his book Derivations, is a Greek word pronounced "autentin" which in Latin means "worthy of faith and obedience." Thus "author," in this derivation, is used for any person deserving of being believed and obeyed. From this comes the word which we are presently treating, namely "authority"; hence we can see that authority means "pronouncement worthy of faith and obedience." Consequently, when I prove that Aristotle is most worthy of faith and obedience, it will be evident that his words are the supreme and highest authority.