They will say, for instance, that “the known (maʿlūm) is derived from knowledge, and grasping the derivative is contingent upon grasping what it is derived from; therefore, if one defines the derivative in terms of its source, a vicious circle results.” Or they will assert, “Knowledge is awareness,” which is no more than a verbal definition. Or they will object, “Your phrase ‘as it truly is’ is a superfluous addition.”
They further argue that inserting truth and falsehood—or affirmation and denial—into the very definition of a report is inadmissible, for truth and falsehood are themselves the two kinds of report, and each can only be explained by reference to the notion of reporting. Hence, defining ‘report’ by them would be circular. Such are the familiar objections continually raised against the familiar definitions.
Some go so far as to claim that these notions cannot—or need not—be defined at all, that they are self-sufficient and above definition. Thus it is said of knowledge that nothing other than knowledge can be known except through knowledge; so if knowledge were defined by something other than itself, circularity would ensue. Or they say, “The very conception of knowledge can only be obtained through knowledge, and that very act presupposes knowledge; therefore, if conceiving knowledge depended on anything else, a circle would arise.”
Likewise, when they speak of defining knowledge, report, or command, they argue: every person is aware of his own hunger and satiety and knows that he knows them; and composite awareness must be preceded by simple awareness. Therefore, everyone already knows what knowledge is, and its conception is self-evident. In the same vein, they say about command and report that everyone can issue a command or give a report and can recognize that this utterance is a command and that one a report, while composite awareness is prior to simple awareness.
The answer given to them is that knowing a particular report or a particular command does not entail knowing what the definition seeks to capture, for the purpose of a definition is to identify the universal essence that is both comprehensive and exclusive. Conceiving a particular only necessitates an unqualified conception of the reality, without the condition of universality and exact correspondence; for the essence itself does not exist