Your quote is not accurate, or it's just absurd. If at first there was "multitude of self", then how could it divide and forget itself, for this "multitude of I" was already a multitude, that is, it was already divided. Generally speaking, this sounds like common pantheism ("omniscience"), in which the original Absolute forgets itself:falls asleep:separates and arises "a multitude of spirits", which, after a certain period of time "...merge into the Absolute.." and disappear. Philosophically such pantheism would correspond to Hegelianism in the first place, and perhaps partially to Schopenhauer's conception of "the world will".