  What we find when we look within ourselves is that we are pointed above to God, who is the light of the mind, guaranteeing the certainty of our judgments. This thesis, usually called by scholars divine illumination, was quite ancient by Bonaventure’s time; it was part of the philosophical teaching of Augustine. What makes Bonaventure’s version so philosophically distinctive is that he proposes to synthesize the epistemology of divine illumination with the Aristotelian account of abstraction. Bonaventure is thoroughly committed to the integral role played by the agent and possible intellects in human intellectual cognition. The agent and possible intellects are not separated substances, in the way envisaged by Averroes, but properly human faculties essential to the constitution of the human soul.  [33]  Hence, unlike his contemporaries, who often thought of the human possible intellect as being illumined by God functioning as an agent intellect, Bonaventure assigns each human being an agent intellect. Differing from other of his contemporaries, Bonaventure also insists that the possible intellect always remains the recipient of the intelligible species abstracted by the agent intellect and the faculty of apprehension; accordingly, the possible intellect continues to be part of the human soul even when the soul is separated by death from the  body.[34]  Abstraction is, for Bonaventure, the source of our concepts of things. How then does illumination work and why is it necessary? The divine light works together with the human intellectual faculties as a “regulative and moving cause,” ensuring that the human mind grasps the immutable truth of the creature; it does not and cannot replace the human intellectual faculties in their proper  roles.[35]  The appeal to divine illumination is justified, primarily if not exclusively, for the reason that there is an incommensurability between our intellectual faculties and the ordinary objects we know as created and mutable, on the one hand, and the immutable truths we come to know. Inasmuch as things cannot give what they do not have, the only source of eternal and immutable truth is God’s Light.