Both Stephen R. Donaldson and P. D. Ouspensky are known for esotericism?
P. D. Ouspensky Pyotr Demianovich Ouspenskii (known in English as Peter D. Ouspensky, Пётр Демья́нович Успе́нский; 5 March 1878 – 2 October 1947), was a Russian mathematician and esotericist known for his expositions of the early work of the Greek-Armenian teacher of esoteric doctrine George Gurdjieff, whom he met in Moscow in 1915. He was associated with the ideas and practices originating with Gurdjieff from then on. He shared the (Gurdjieff) "system" for 25 years in England and the United States, having separated from Gurdjieff in 1924 personally, for reasons he explains in the last chapter of his book "In Search of the Miraculous".
The Over-Soul "The Over-Soul" is an acclaimed essay by Ralph Waldo Emerson, first published in 1841. With the human soul as its overriding subject, several general themes are treated: (1) the existence and nature of the human soul; (2) the relationship between the soul and the personal ego; (3) the relationship of one human soul to another; and (4) the relationship of the human soul to God. Influence of Eastern religions, including Vedantism, is plainly evident, but the essay also develops ideas long present in the Western tradition, e.g., in the works of Plato, Plutarch, and Neoplatonists like Plotinus and Proclus – all of whose writings Emerson read extensively throughout his career – and Emanuel Swedenborg.