An excerpt from The Science of Seership by Geoffrey Hodson. Written in 1929.
How to become psychic
"Any expansion of consciousness is valueless unless the personal
vehicles of thought, feeling and action are sufficiently refined to
receive and express its results. In order to achieve refinement of the
vehicles a strictly ethical and aesthetic mode of life must be adopted;
everything which is contrary to the highest ethical and cultural ideals
must be avoided. All tendency to coarseness and self-indulgence must be
gradually eliminated. The mind must be purified by pure thinking, and
the feelings cleansed by resistance to every impure emotion. The body,
in its turn, must be made healthy, responsive and as pure as possible
by scrupulous personal cleanliness, a pure diet, and complete obedience
to the laws of health.
Those who make this attempt will nearly always adopt a fleshless diet, because, as they find the sense of the unity of all life growing within them, it will become impossible for them to eat the dead bodies of their animal brothers. Further, if matter which is vibrating at a lower rate than that of the human body is taken for food, the bodily power of response is decreased; a flesh diet therefore interferes seriously with the development of seership.
In addition to the coarser vibrations of the matter of animal bodies, there are also present the terrible vibrations of cruelty, horror, pain and agonizing fear, which are inseparable from the use of flesh as food. By putting flesh into our bodies we are really desecrating the temple of the Most High. The law of life is the law of love, not of death. If we choose the way of life its laws must be obeyed, for disaster will quickly follow disobedience.
These laws may be summed up as purification of thought, refinement of feeling, and control of bodily conduct. The neophyte must settle down to steady self-training, never forgetting the object in view, which is the development to the highest possible degree of will power, wisdom and knowledge, and the attainment of the glorious goal of ever-widening fields of service."