that actually exist, when we subsume existing things under a universal principle, as in the sciences of religious law, medicine, and so forth.

A physician’s knowledge that scammony expels yellow bile and that blood is removed through venesection and cupping does not yield knowledge of what will benefit people unless he knows that this person suffers from yellow bile and that another has an excess of blood.

When he knows particulars as well as universals, he benefits from his knowledge and can bring about effects in the world. His knowledge then becomes productive—that is, a prerequisite for action.

Universal knowledge, however, without knowledge of the particulars upon which the agent acts, is not productive knowledge and has no effect upon anything’s existence or upon the agent’s action.

This makes it clear that their claim that the knowledge of the Lord, exalted is He, is productive, while excluding actually existing particulars from it, involves a contradiction apparent to anyone who understands the two assertions.

Most of their claims are contradictory. Their error concerning knowledge, however, is immense: it is among the vilest forms of unbelief and the most contrary to clear reason and the innate disposition Allah has given His servants.

He also says:

“Zayd as an individual is distinguished from Amr as an individual only by sense perception, not by the intellect. For distinction rests upon pointing in a particular direction, whereas the intellect apprehends direction in its unqualified, universal sense, and place in its universal sense.

“As for our saying ‘this’ and ‘this,’ it points to a relation between the object perceived and the perceiver, in that the object is near to him, far from him, or in a particular direction.”