Abū al-Qāsim al-Anṣārī, in his Commentary on al-Irshād, quotes:

“Imām al-Ḥaramayn said: ‘In the terminology of the speculative theologians, the purpose of formulating a definition is to identify a thing’s distinctive property and true reality—that by which it is set apart from everything else.’”

The Master added:

“‘The definition of a thing is the meaning for the sake of which it possesses the attribute under discussion.’”

Abū al-Maʿālī went on to say:

“‘If someone were simply to state, “The definition of a thing is its meaning,” he would be correct; and were he to say, “The definition of a thing is its reality or its special property,” that too would be acceptable.’”

He continued:

“‘Should it be objected: “When you speak of ‘the definition of knowledge’ or ‘the reality by which something is known,’ you do not mention the unique property of knowledge, for knowledge encompasses both disparate and similar instances, and these cannot all be gathered under a single particular property—indeed, whatever shares the most specific property is, by definition, alike.”

“We reply: Our only aim is to show that what we have called a definition is the distinctive description of the thing defined for the purpose at hand. The question is not seeking a detailed breakdown of knowledge; rather, it wishes to grasp ‘knowledge-ness’ by means of the most specific description common to every form of knowledge, whether they differ or resemble one another. This is why we expressed it as ‘cognition,’ or ‘that by which something is known,’ or ‘disclosure.’”’

This reflects the Master’s method: anyone who attempts to give a definition within the realm of intelligibles is merely trying to pinpoint an attribute common to the class in question in a manner clear to the questioner.

Abū al-Maʿālī further said:

“‘If it is asked whether a definition ultimately concerns the speaker’s words or an attribute inherent in the thing defined, we answer: all the leading scholars agree that the definition is an attribute of the thing defined—whether or not the describers articulate it. In this sense, it is identical with the thing’s reality.’”

The Qāḍī states in al-Taqrīb that “a definition is the statement of the one defining, informing about the attribute shared by the individual instances of the thing defined.” Yet he concurs with our colleagues that the reality and meaning of a thing refer back to an attribute, not to the words of the speaker. He only expressed it in terms of a “definition” because it resembles a description, just as reality resembles an attribute; still, we distinguish between a description (waṣf) and an attribute (ṣifah).

The Qāḍī then remarks: “Some things admit of definition while others do not, although everything that truly exists has a reality of its own. Thus, whoever holds that a definition ultimately returns to the very reality of the thing defined is in the right.”