Know that the difficulties which lead to confusion in the question what is the purpose of the Universe or of any of its parts, arise from two causes: first, man has an erroneous idea of himself, and believes that the whole world exists only for his sake; secondly, he is ignorant both about the nature of the sublunary world, and about the Creator's intention to give existence to all beings whose existence is possible, because existence is undoubtedly good.

Ch.25 - Guide for the Perplexed (c. 1190) - Part III