we were to suppose this, no impossibility would ensue.’ Yet the very conditional premise is unknown, for it is not self-evident that nothing objectionable follows from it, nor have they furnished any rational proof to that effect.
Even further from sound reasoning is the path taken by some philosophers and theologians—such as Ibn Sīnā, al-Rāzī, and their like—who seek to establish external possibility merely because a thing can be conceived in the mind. When Ibn Sīnā and his followers wished to prove that there exists outside the mind an intelligible entity that is never perceived by the senses, they argued from the concept of the absolute, universal ‘man,’ which encompasses the individual men found in the world. All this shows, however, is that such intelligibles can exist in the mind, for a universal exists as a universal only in the intellect. That is not the point under dispute; the real question is whether such an intelligible can exist externally. Not everything the mind can conceive exists outside the mind as conceived, for the intellect can imagine things whose existence is impossible, such as combining contraries or contradictories.
Al-Rāzī adopted this very proof, and he and others went on to argue for the same possibility by saying: ‘An existent is either contiguous to something else, or separate from something else, or neither contiguous nor separate.’ They imagined that because the intellect can frame this tripartite division, each of its branches must be possible in external reality. This is erroneous. It is like saying: ‘An existent is either necessary, contingent, or neither;’ or ‘either eternal, originated, or neither;’ or ‘either self-subsistent, dependent on another, or neither.’ Such mental classifications do not prove the possibility of an existent that is neither necessary nor contingent, neither eternal nor originated, neither self-subsistent nor dependent on something else. The same criticism applies to their earlier argument.
How far, then, are these methods of establishing external possibility from the method of the Qur’an!