"I don't believe that Dick has any subconscious self," said Mary.
"Oh yes, he has. Only, people who have led his kind of life have their ordinary self so well managed and disciplined--their wits so much about them, as the phrase goes--that the subconscious rarely gets a show. But I bet if Dick took to thinking about his soul, which he never does, he would find some queer corners. Take my own case." He turned towards me so that I had a full view of his candid eyes and hungry cheek-bones which looked prodigious in the firelight. "I belong more or less to the same totem as you, but I've long been aware that I possessed a most curious kind of subconsciousness. I've a good memory and fair powers of observation, but they're nothing to those of my subconscious self. Take any daily incident. I see and hear, say, about a twentieth part of the details and remember about a hundredth part--that is, assuming that there is nothing special to stimulate my interest. But my subconscious self sees and hears practically everything, and remembers most of it. Only I can't use the memory, for I don't know that I've got it, and can't call it into being when I wish. But every now and then something happens to turn on the tap of the subconscious, and a thin trickle comes through. I find myself sometimes remembering names I was never aware of having heard, and little incidents and details I had never consciously noticed. Imagination, you will say; but it isn't, for everything that that inner memory provides is exactly true. I've tested it. If I could only find some way of tapping it at will, I should be an uncommonly efficient fellow. Incidentally I should become the first scientist of the age, for the trouble with investigation and experiment is that the ordinary brain does not observe sufficiently keenly or remember the data sufficiently accurately."
"That's interesting," I said. "I'm not at all certain I haven't noticed the same thing in myself. But what has that to do with the madness that you say is infecting the world?"
"Simply this. The barriers between the conscious and the subconscious have always been pretty stiff in the average man. But now with the general loosening of screws they are growing shaky and the two worlds are getting mixed. It is like two separate tanks of fluid, where the containing wall has worn into holes, and one is percolating into the other. The result is confusion, and, if the fluids are of a certain character, explosions. That is why I say that you can't any longer take the clear psychology of most civilised human beings for granted. Something is welling up from primeval deeps to muddy it."
"I don't object to that," I said. "We've overdone civilisation, and personally I'm all for a little barbarism. I want a simpler world."
"Then you won't get it," said Greenslade. He had become very serious now, and was looking towards Mary as he talked. "The civilised is far simpler than the primeval. All history has been an effort to make definitions, clear rules of thought, clear rules of conduct, solid sanctions, by which we can conduct our life. These are the work of the conscious self. The subconscious is an elementary and lawless thing. If it intrudes on life two results must follow. There will be a weakening of the power of reasoning, which after all is the thing that brings men nearest to the Almighty. And there will be a failure of nerve."
The above from "The Three Hostages" by John Buchan, and largely correct. The subconscious has unusual powers to which the conscious mind has no access, and nor should it. Those who seek to access them generally attempt it through the subordination of the will, the ego. Never was a worse crime against nature commited than this buddhist nonsense.
Subordinating one's will leaves you open to outside forces, such as demons, and to the flesh. It makes you weak, effeminate. What we need is to impose the will upon the mind.
Every people in history has had physical exercise designed to aid the strengthening not of the body but of the control of the mind over the body, I mean martial arts like capoeira and glima or Gurdjieff exercises.