"Anything that is secret and mysterious in these systems of Yoga should be at once rejected. The best guide in life is strength. In religion, as in all other matters, discard everything that weakens you, have nothing to do with it. Mystery-mongering weakens the human brain. It has well-nigh destroyed Yoga - one of the grandest of sciences. From the time it was discovered, more than four thousand years ago, Yoga was perfectly delineated, formulated, and preached in India. It is a striking fact that the more modern the commentator the greater the mistakes he makes, while the more ancient the writer the more rational he is. Most of the modern writers talk of all sorts of mystery. Thus Yoga fell into the hands of a few persons who made it a secret, instead of letting the full blaze of daylight and reason fall upon it. They did so that they might have the powers to themselves."

- Swami Vivekananda, "Introductory" (Dec 14, 1895, New York Vedanta Society), Raja-Yoga, Complete Works: Vol 1