The purpose here is to show that nothing established by reason contradicts what the Messenger, may Allah bless him and grant him peace, brought.

It is known that those who claim that reason contradicts it fall into two groups:

One group considers it possible that he and the other messengers spoke falsely, whether deliberately or mistakenly, in what they reported concerning Allah Most High and conveyed from Him to the nations, or that they outwardly expressed the opposite of what they inwardly held. Such views are held by some who disbelieve in the messengers and by some who outwardly profess belief in them, including hypocrites among the philosophers, the Qarmatians, the esotericists, and others who hold any such view.

The other group does not consider such things possible for the messengers. This is the position of the speculative theologians who affiliate themselves with Islam, in all their varieties.

The proponents of religious innovation among them err both in their understanding of revelation and in their reasoning. Regarding revelation, they attribute to the Messenger, may Allah bless him and grant him peace, things he did not say, whether deliberately or mistakenly. Regarding reason, they substantiate these claims with what they suppose to be demonstrative proofs.

If a claim is false, the argument supporting it can only be invalid. For evidence is a necessary concomitant of what it indicates, and a necessary consequence of truth can only be true. Falsehood, however, may have a true consequence. Thus, a true claim is sometimes supported by a sound argument and sometimes by an unsound one, whereas a false claim can only be supported by an unsound argument. For if its argument were sound, falsehood would necessarily follow from truth, which is impossible,