 On the other hand, just as senses are the right judges of their own proper sensible—the eye of color and light, the ear of sound, etc.—human intellect also possesses an internal criterion which allows it to judge its own objects rightly. It has the use of “a spiritual and universal light that it has of its own nature since the commencement of its creation” (VS: 193). Here the inspiration is clearly Augustinian, as it is for Descartes’s parent conception of “lumière naturelle”. The light of the soul does not give men direct access to divine knowledge, knowledge of essences, as that would require an eternal glory and a supernatural light. But it still gives access to a number of evidentia, immediate certainties, whose truth, Mersenne concedes, depends on God’s illumination and God’s veracity. Thus, in every realm of knowledge or human interests, there are truths that are not capable of doubt, such as “the whole is greater than the part”, or “evil should be avoided”.