“Reality is merely an illusion, albeit a very persistent one.”

Source: The Technological Society (1954), p. 139

Make Your Own 3D Illusions (2014).
Context: We long for a technological world, while keeping the natural aspect of our environment; we want the progress, while maintaining the traditions; we want organization while preserving individual freedom; we produce at a large scale while looking for unique products; we want clearness in our relationships, while we like to play with the ambiguity; we wish everlasting happiness while seeking incomparable magic moments… In reality, from all these contradictions, we are looking for only one thing: ASTONISHMENT. We would life to astonish us every day! That’s why we all, human beings, love playing, because games are synonymous of risk and astonishment. Games are enactments, and the act of playing is an illusion of the illusion of the reality.

Source: The Void Captain's Tale (1983), Chapter 13 (p. 164)

Source: The Void Captain's Tale (1983), Chapter 14 (p. 177)

As translated at Gallery of Russian Thinkers … selected by Dmitry Olshansky (2005)<!-- by Richard Schain --> http://www.isfp.co.uk/russian_thinkers/nikolay_berdyaev.html
Dream and Reality (1949)
Context: There is no objective reality. But there is only an illusion of consciousness, there is only an objectivication of reality, which was created by the spirit. The origin of life is creativity, freedom; and the personality, subject, and spirit are the representatives of that origin, but not the nature, not the object.

Source: One Minute Nonsense (1992), p. 131
Context: The Master persistently warned against the attempt to encompass Reality in a concept or a name. A scholar in mysticism once asked, "When you speak of BEING, sir, is it eternal, transcendent being you speak of, or transient, contingent being?"
The Master closed his eyes in thought. Then he opened them, put on his most disarming expression, and said, "Yes!"

Source: History and Class Consciousness (1968), p. 13