The sort of philosophy that the Islamic world discovered when it came into contact with the main centers of civilization in the Middle East was neoplatonism. This represented a long tradition of philosophy that had as one of its main planks a theory of how the world is linked with its ultimate cause. Emanation is an important neoplatonic concept that provides an account of this relationship. The existence of this world and the other worlds that exist along with it are taken to flow from the ultimate cause, the One that is the cause of multiplicity, and a main difference from a normal causal relationship is that the cause and the effect are often taken to occur at the same time as each other. This is because emanation represents an eternal process, not only bringing other things into existence but also sustaining their continuing existence.

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