“Why do you mix truth with falsehood and conceal the truth while you know it?” [Āl ‘Imrān: 71]

Or it may contain something that seems plausible to those who uphold falsehood, although it is false and its falsity becomes clear upon sound examination. Such was the case with those who said that Muhammad, may Allah bless him and grant him peace, was a poet, a soothsayer, and a madman. They called him a poet because poetry is metrical, rhyming speech, and they likened the Quran to it in this respect. A soothsayer occasionally makes a prediction that proves true, so they likened the Messenger to him in this respect. A madman says and does things contrary to the understanding of rational people. Thus, when they claimed that what the Messenger, may Allah bless him and grant him peace, brought was contrary to what rational people would bring, they accused him of madness.

Yet the proofs Allah establishes and the knowledge to which He guides His servants distinguish truth from the falsehood with which it may be confused. However, not everyone who knows the truth—whether through immediate knowledge or reasoned inquiry—can present an opponent with an argument that guides him or refutes him conclusively. The means by which a person comes to know the truth are one thing, and the means by which he enables someone else to know it are another. Not everything a person knows can be conveyed by him to others. Thus, inquiry has a broader scope than debate: every argument that can be used in debate can be examined through inquiry, but not everything that can be examined through inquiry can be used in debate with every person.