Abstract
Descartes’ “natural light” has been interpreted as a faculty of the mind, the sense-imagination-reason-under-standing composite, the principle of intellectual integrity and growth, or even God himself. In Meditations III and IV in particular, the meaning of lumen natural depends on recognizing how light and nature define one another and how “my nature” serves as the basis for pointing to what is beyond the domain of natural reason, including religious faith and natural belief (especially regarding morality).