Thank you very much for putting comment. Human beings recognize the existence of things by experiencing and comparing two different situations. For example, we recognize darkness in case there is no light in a place. We contrast colours because they have different effects on our eyes. If all things on the Earth were green, we couldn't recognize anything. In this case, even greenness made no sense.
As a rule, we identify things by means of their opposites. If there was something in the world which has no opposite we couldn't either realise or recognise it!
In answering to your question it should be said that year made no sense if there were no seasons; seasons couldn't be contrasted if there was no change in climate. Swimming easily and happily in the sea, a fish is not able to realise what water is. If you'd like to teach a fish how to recognise water, you'd remove it from the sea and put it on the ground. It would realise the existence of water!
Human beings cannot realise the existence of God, due to the fact that God has not got an opposite. We are quite similar to the fish in the sea. We cannot understand how would a place be if there wasn't God. Our situation is much worse than the situation of the fish, because the fish could at least experience a place without water, although it died. However, human beings never can experience a place without God(a Godless place).
This is so philosophical. I dislike to bother you. I hope not to sound religious and not to cause the thread an early ban by writing such philosophical things.
All the best,
Behnam, 24 January, 2012