Thus, there is a dualism between the true aspect of everything and the physical side, false but ineluctable, with each evolving into the other: as God must compress and disguise himself, so must humans and matter in general ascend and reunite with the omnipresence. Rachel Elior quoted Shneur Zalman of Liadi, in his commentary "Torah Or" on Genesis 28:21, who wrote that ""this is the purpose of Creation, from Infinity to Finitude, so it may be reversed from the state of Finite to that of Infinity"". Kabbalah stressed the importance of this dialectic, but mainly (though not exclusively) evoked it in cosmic terms, referring for example to the manner in which God progressively diminished himself into the world through the various dimensions, or "Sephirot". Hasidism applied it also to the most mundane details of human existence. All Hasidic schools devoted a prominent place in their teaching, with differing accentuation, to the interchanging nature of "Ein", both infinite and imperceptible, becoming "Yesh", "Existent" – and vice versa. They used the concept as a prism to gauge the world, and the needs of the spirit in particular. Elior noted: ""Reality lost its static nature and permanent value, now measured by a new standard, seeking to expose the Godly, boundless essence, manifest in its tangible, circumscribed opposite.""