"Real rationalism,

that is to say, reverence for the miracle of 'aql, must include a belief in innate knowledge, since the experiences of the senses are inadequate in explaining how we have come to know certain things. There are certain truths, such as the mathematical, which we experience as intuitive and rooted in an innate knowledge. Ethical knowledge also seems to be a priori: [38] it proceeds from 'aql as understood as the wise perception of the human totality (kamil), including the corporeal (what Merleau-Ponty calls the ‘body-subject’). True reason, 'aql, is therefore a knowledge by recollection (dhikr); and again this calls Plato to mind. [39]  What we know, where it matters, is what we have managed to remember, which is why the Prophet is ‘only a reminder’ (88:21), and the Qur’an is ‘a reminder; and whoever wishes, will remember’ (84:54). To achieve this ‘remembering’, and therefore to account for the apparent mystery of our a priori knowledge of axioms and ethics, [40]  we are required to exist in a harmonious balance which incorporates body, intellect and soul into a single human subject, an omnium, al-insan al-kamil. Only such a being is capable of true reason, of 'aql.

-from pgs. 10-11 of Shaykh Abdal-Hakim Murad's "Reason as Balance: the evolution of 'aql" (a paper for the Cambridge Muslim College)