Eighth Category: Refutation of their claim that the intellect, by itself, cannot pass judgment in matters that are commonly acknowledged.

He says:
“Take note: pleasure is the perception and attainment that accompany the arrival of something the perceiver regards as perfection and goodness as such, whereas pain is the perception and attainment that accompany the arrival of something the perceiver regards as deficiency and evil as such. Good and evil may vary by comparison: the object that appetite deems good is, for example, agreeable food or a pleasant touch; the object that anger deems good is victory; and the object that the intellect deems good is, at one time and from one angle, truth, and at another time and from another angle, beauty. Among the intellectual goods are the attainment of gratitude, an abundance of praise, commendation, and honor. In short, the aims of people of intellect differ in this respect.

Every good thing, in relation to a particular entity, is the perfection proper to it toward which it inclines by virtue of its original disposition, and every pleasure is tied to two matters: a beneficial perfection and the perception of it as such.”

It is therefore said to him:
“This is a plain admission that the intellect loves truth and delights in it, and loves beauty and delights in it, and that love of praise, gratitude, and generosity is an intellectual matter. This is indeed correct, for the human being possesses two faculties: a cognitive faculty that loves truth, and a practical faculty that loves beauty—the beautiful being what is fair, while the ugly is its opposite.

His separating ‘truth’ from ‘beauty’ is merely a question of terminology; in the language of the Quran and in the speech of the Messenger, the word ḥaqq (truth) embraces both, as in his saying, peace and blessings be upon him: