"You may suddenly come to see, in a flash, the profound rightness of the basic conviction in Vedanta: it is not possible that this unity of knowledge, feeling, and choice which you call your own should have sprung into being from nothingness at a given moment not so long ago; rather this knowledge, feeling, and choice are essentially eternal and unchangeable and numerically one in all men, nay in all sensitive beings. But not in this sense—that you are a part, a piece, of an eternal, infinite being, an aspect or modification of it, as in Spinoza’s pantheism. For we should then have the same baffling question: which part, which aspect are you? What, objectively, differentiates it from the others? No, but, inconceivable as it seems to ordinary reason, you—and all other conscious beings as such—are all in all. Hence this life of yours which you are living is not merely a piece of the entire existence, but is, in a certain sense, the whole; only this whole is not so constituted that it can be surveyed in one single glance. This, as we know, is what the Brahmins express in that sacred, mystic formula which is yet really so simple and so clear: Tat tvam asi, this is you. Or, again, in such words as “I am in the east and in the west, I am below and above, I am this whole world.”"
January 1, 1970
https://en.wikiquote.org/wiki/Erwin_Schr%C3%B6dinger