P. D. Ouspenskys ‘The Psychology of Mans Possible Evolution’ was published shortly after his death in 1947 together with In Search of the Miraculous. It describes how and why man must work simultaneously on his knowledge and his being to find inner unity. From the book:
And here we come at once to a very important fact. Man does not know himself. He does not know his own limitations and his own possibilities. He does not even know to how great an extent he does not know himself.
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