In the third century, Plotinus recast Plato's system, establishing Neoplatonism, in which Middle Platonism was fused with mysticism. At the summit of existence stands the One or the Good, as the source of all things. It generates from itself, as if from the reflection of its own being, reason, the "nous", wherein is contained the infinite store of ideas. The world-soul, the copy of the "nous", is generated by and contained in it, as the "nous" is in the One, and, by informing matter in itself nonexistent, constitutes bodies whose existence is contained in the world-soul. Nature therefore is a whole, endowed with life and soul. Soul, being chained to matter, longs to escape from the bondage of the body and return to its original source. In virtue and philosophical thought it has the power to elevate itself above the reason into a state of ecstasy, where it can behold, or ascend to, that one good primary Being whom reason cannot know. To attain this union with the Good, or God, is the true function of human beings.