that is put into practice, and to action based on knowledge. Hence the inhabitants of the Fire will say:

“If only we had listened or reasoned, we would not have been among the companions of the Blaze.”

And the Most High says:

“Have they not travelled through the land so that they may have hearts with which to reason?”

Reason, as a prerequisite for religious accountability, must consist in knowledge by which a person distinguishes between what benefits him and what harms him. A mentally unsound person who cannot distinguish between dirhams and copper coins, distinguish the days of the week, or understand what is said to him does not possess reason. Someone who understands speech and distinguishes between what benefits him and what harms him, however, possesses reason.

Some people say that reason consists in necessary knowledge, while others say that it consists in acting in accordance with what that knowledge requires. The correct view is that the term “reason” encompasses both. Reason may also refer to the innate faculty within a person by which he knows, distinguishes, and seeks what is beneficial rather than harmful. As Ahmad ibn Hanbal, al-Hārith al-Muhāsibī, and others have said, reason is an innate faculty.

The majority of rational people affirm the existence of this innate faculty, just as the majority of rational people affirm that the eye possesses a faculty by which one sees, the tongue a faculty by which one tastes, and the skin a faculty by which one feels through touch. Some people deny faculties and natural properties, as is the position of Abū al-Hasan and those who followed him among the adherents of Mālik, al-Shāfi‘ī, Ahmad, and others. And those who deny faculties and natural properties