The Greeks also had theories on light, its properties and its speed. They thought light did not have movement or speed, because if it did, the speed would be too great to contemplate. They concluded that light must simply either be there or not be there. Aristotle, the famous Greek natural philosopher, said that "...light is neither fire nor any kind whatsoever of body nor an efflux from any kind of body ... It is certainly not a body, ... clearly therefore, light is just the presence of that [or light is simply the presence of light itself]. Empedocles (and with him all others who used the same forms of expression) was wrong in speaking of light as 'traveling' or being at a given moment between the earth and its envelope, its movement being unobservable by us; that view is contrary both to the clear evidence of argument and to the observed facts; if the distance traversed were short, the movement might have been unobservable, but where the distance is from extreme East to extreme West [i.e. at dawn light fills the entire sky which is a great distance therefore], the draught upon our powers of belief is too great." -- Aristotle "On the Soul" Book 2, Part 7. (Note: comments in brackets added for clarification.)
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