" Philosophers and fools might claim that light is without shape, that it finds its existence in painting the shape of other things, as wayward as the opening of an eye. That, in the absence of such things, it slants unseen, indeed, invisible. Without other things to strike upon, it does not cavort, does not bounce, does not paint and reflect. Rather, it flows eternal. If this is so, then light is unique in the universe.
But the universe holds to one law above all others: nothing is unique.
Fools and philosophers have not, alas, seen the light. "

― Steven Erikson , Toll the Hounds (Malazan Book of the Fallen, #8)