It is therefore said: these are concrete particulars, not universals. Now, if the soul endures so long as the object it knows endures, then the only object of knowledge that is truly abiding—pre-eternal, everlasting, beyond all doubt as to its persistence and pre-existence—is the Lord of all worlds. Hence true felicity and perfection lie in knowing Him and worshipping Him. This is the supreme science: knowledge of the Most High Lord. Knowledge is not, as these philosophers and those who follow them maintain, the study of an unqualified “existence” and its divisions—a notion that even al-Rāzī and others worked into the principles of jurisprudence, adducing demonstrations that refer everything back to the “higher science” that investigates being and its concomitants.
Elsewhere we have treated at length their discussions of definition (ḥadd) and demonstration (burhān) and have set out the position of Muslim dialecticians on definition: its aim is to distinguish the thing defined from everything else. In other words, it unpacks what the name indicates only in a general way—whether the definition be of a term (definition according to name) or of an existent entity (definition according to reality). Such a definition is established through common usage that matches the definiendum in both extension and intension, so that the presence of either entails the presence of the other and its absence entails its absence; thus the definition is both inclusive and exclusive, just as the name corresponds to the thing named.
As for their claim that a definition provides knowledge of the external reality of the thing defined, and that it must consist of essential attributes combined from genus and differentia, Muslim dialecticians have shown its errors from several angles, as we have explained elsewhere. We clarified that when they say, “Man is composed of genus and differentia,” this is correct only with respect to what exists in the mind: when a person conceives of man as a rational animal, what he conceives is indeed a mental composition of these two elements, whereas