As stated in the Introduction to this work, I have little personal doubt, after a careful and unbiassed appreciation of all the evidence, that the _Magnum Opus_ has been performed, at least occasionally, in the past, and that, therefore, the alchemists, while laying the foundations of modern chemistry, had already transcended its highest results in the metallic kingdom. Now, the Hermetic doctrine of correspondences which is, at any rate, entitled to the sincere respect of all esoteric thinkers, will teach us that the fact of their success in the physical subject is analogically a substantial guarantee of the successful issue of parallel methods when applied in the psychic world with the subject man. But the revelations of mesmerism, and the phenomena called spiritualism, have discovered thaumaturgic possibilities for humanity, which in a wholly independent manner contribute to the verification of the alchemical hypothesis of development in its extension to the plane of intelligence. These possibilities I believe to be realizable exclusively along the lines indicated in Hermetic parables. I am not prepared to explain how the alchemical theory of Universal Development came to be evolved in the scientific and psychological twilight of the middle ages, but the fact remains. Nor am I prepared to explain how and why the method of a discredited science which is not commonly supposed to have attained its end, should not only be consistent within its own sphere, but should have a vast field of application without it; yet, again, the fact remains. I have brought a wide acquaintance with the history of modern supernaturalism to bear on the serious study of alchemy, and have found the old theories illustrated by the novel facts, while novel facts coincided with old theories. As all this has occurred, in the words of the alchemists, “by a natural process, devoid of haste or violence,” I may trust that it is no illusory discovery, and that its future enunciation may give a new impulse to the study of the Hermetic writings among the occultists of England and America. FOOTNOTES: