In The Doors of Perception Aldous Huxley has given us a superbly written account of the effects of mescalin upon a highly sensitive person. It was a record of his first experience of this remarkable transformation of consciousness, and by now, through subsequent experiments, he knows that it can lead to far deeper insights than his book described. While I cannot hope to surpass Aldous Huxley as a master of English prose, I feel that the time is ripe for an account of some of the deeper, or higher, levels of insight that can be reached through these consciousness-changing "drugs" when accompanied with sustained philosophical reflection by a person who is in search, not of kicks, but of understanding. I should perhaps add that, for me, philosophical reflection is barren when divorced from poetic imagination, for we proceed to understanding of the world upon two legs, not one. It is now a commonplace that there is a serious lack of communication between scientists and laymen on the theoretical level, for the layman does not understand the mathematical language in which the scientist thinks. For example, the concept of curved space cannot be represented in any image that is intelligible to the senses. But I am still more concerned with the gap between theoretical description and direct experience among scientists themselves. Western science is now delineating a new concept of man, not as a solitary ego within a wall of flesh, but as an organism which is what it is by virtue of its inseparability from the rest of the world. But with the rarest exceptions even scientists do not feel themselves to exist in this way. They, and almost all of us, retain a sense of personality which is independent, isolated, insular, and estranged from the cosmos that surrounds it. Somehow this gap must be closed, and among the varied means whereby the closure may be initiated or achieved are medicines which science itself has discovered, and which may prove to be the sacraments of its religion. For a long time we have been accustomed to the compartmentalization of religion and science as if they were two quite different and basically unrelated ways of seeing the world. I do not believe that this state of doublethink can last. It must eventually be replaced by a view of the world which is neither religious nor scientific but simply our view of the world. More exactly, it must become a view of the world in which the reports of science and religion are as concordant as those of the eyes and the ears. But the traditional roads to spiritual experience seldom appeal to persons of scientific or skeptical temperament, for the vehicles that ply them are rickety and piled with excess baggage. There is thus little opportunity for the alert and critical thinker to share at first hand in the modes of consciousness that seers and mystics are trying to express—often in archaic and awkward symbolism. If the pharmacologist can be of help in exploring this unknown world, he may be doing us the extraordinary service of rescuing religious experience from the obscurantists, To make this book as complete an expression as possible of the quality of consciousness which these drugs induce, I have included a number of photographs which, in their vivid reflection of the patterns of nature, give some suggestion of the rhythmic beauty of detail which the drugs reveal in common things. For without losing their normal breadth of vision the eyes seen to become a microscope through which the mind delves deeper and deeper into the intricately dancing texture of our world.