When one makes his intellect the dominant force in his decision-making [as opposed to his natural physical desires] this impresses itself upon the world and adds light and purity - to the extent that this person bears influence over existence [different people have different status when it comes to their influence over reality].
An even higher level is when a person's NATURE is to guide his life based on his intellect. This generates the appearance of hidden Divine light which transforms much evil into goodness.
