“The encompassing, creative mind recognizes no boundaries. The mind has ever brought new spheres under its control.
All our experiences culminate in the perception of the universe as a whole, with man as its center.”

Pearls of Wisdom

The Notebooks of Leonardo da Vinci (1883), XIX Philosophical Maxims. Morals. Polemics and Speculations.

Source: The Responsible Self: An Essay in Christian Moral Philosophy (1963), p. 61

East of Eden (1952)
Context: Our species is the only creative species, and it has only one creative instrument, the individual mind and spirit of a man. Nothing was ever created by two men. There are no good collaborations, whether in art, in music, in poetry, in mathematics, in philosophy. Once the miracle of creation has taken place, the group can build and extend it, but the group never invents anything. The preciousness lies in the lonely mind of a man.
And now the forces marshaled around the concept of the group have declared a war of extermination on that preciousness, the mind of man. By disparagement, by starvation, by repressions, forced direction, and the stunning blows of conditioning, the free, roving mind is being pursued, roped, blunted, drugged. It is a sad suicidal course our species seems to have taken.
And this I believe: that the free, exploring mind of the individual human is the most valuable thing in the world. And this I would fight for: the freedom of the mind to take any direction it wishes, undirected. And this I must fight against: any religion, or government which limits or destroys the individual. This is what I am and what I am about. I can understand why a system built on a pattern must try to destroy the free mind, for it is the one thing which can by inspection destroy such a system. Surely I can understand this, and I hate it and I will fight against it to preserve the one thing that separates us from the uncreative beasts. If the glory can be killed, we are lost.

Source: The Gospel of Sri Ramakrishna (1942), p. 248
Context: It is not good for ordinary people to say, "I am He." The waves belong to the water. Does the water belong to the waves?
The upshot of the whole thing is that, no matter what path you follow, yoga is impossible unless the mind becomes quiet. The mind of a yogi is under his control; he is not under the control of his mind.

Nahj al-Balagha

Source: Memoirs of a Superfluous Man (1943), p. 88

Source: Mind is a Myth (1987), Ch. 1: The Certainty That Blasts Everything
Context: Our mind (and there are no individual minds — only "mind", which is the accumulation of man's knowledge and experience) has created the notion of the psyche and evolution. Only technology progresses, while we as a race are moving closer to complete and total destruction of the world and ourselves. Everything in man's consciousness is pushing the whole world, which nature has so laboriously created, toward destruction. There has been no qualitative change in man's thinking; we feel about our neighbours just as the frightened caveman felt towards his. The only thing that has changed is our ability to destroy our neighbor and his property.

Napoleon : In His Own Words (1916)