There is no doubt, for any observant person, that what is sometimes called a ‘wave’ of mysticism is passing over the world at the present time. It matters not whether you travel in the East or in the West; it matters not whether you look at the churches or at the many bodies outside the recognised churches in Christendom; wherever you look you see the same fact emerging - that men and women are turning away from external proof towards inner realisation; that they are beginning to feel that not the authority from outside but the authority from within ought to be the guiding force of life; that they are beginning to feel that scriptures, however sacred, authority, however venerable, is not  the final word of religion for man. And so on all sides you see a searching, a desire, a longing, to replace faith by knowledge, speculation by certainty.
You may remember, looking over the last year or two, that that which is called Mysticism has met with expositions in this country, and you may remember, perhaps with some feeling of slight amusement, that it was the pronouncement of the Dean of S. Paul’s which induced the Times newspaper to change its attitude to Mysticism. “We had thought,” said the Times, “that Mysticism was an exploded superstition”. It is true that Lord Rosebery had spoken of Cromwell as a practical mystic, and had stated in various ways that the practical mystic was a very terrible person, that he was a man apt to carry everything before him, a man to be reckoned with in the outer world as well as in the inner; but then you would agree with me that a man like Cromwell is not exactly the kind of man that the Times would approve of, unless he lived some centuries ago, and did not cause unrest and disturbance in the eminently respectable society in which the Times desires to live and move. But when a Dean, and not only a Dean, but a Dean of the Metropolis of the Empire, a Dean of S. Paul’s - surely the most respectable of all ecclesiastical dignitaries - when a man like that came out with the statement that “Mysticism is the  most scientific form of religion”, you cannot wonder that under those conditions the Times began to reconsider its view, and perhaps began to think, with some inner disturbance, that Mysticism was rather an explosive superstition than the exploded superstition, the burst and dead shell, which it had hitherto hoped that it was. It had belonged to cranks like Theosophists, to foolish people; but when a Dean pronounced it scientific, then, like mesmerism rebaptised as hypnotism, it could be accepted in respectable society and brought within the purview of the ordinary respectable man.
And so now we can deal with Mysticism without fear of being called superstitious for the dealing, and we may perhaps begin by asking: Why did the Dean of S. Paul’s declare that Mysticism was the most scientific form of religion, why did he remove it from the world of dreams and place it in the broad light of intellect, in the scientific world of fact? For a very clear and definite reason; because Mysticism, like all science, depends on the testimony of consciousness, the only sure testimony that we possess as to the existence of facts without us, as to the existence of an external world at all. It is only from the testimony of consciousness that we can argue that anything exists outside ourselves. Because, when certain impacts are made upon us, consciousness answers to those in various ways, therefore we conclude that
 there is an external world. We do not know that world; we only know the response of consciousness to impressions made upon us from what we presume to be an external world. Many people, because they do not think closely, do not realise that all that they know is the impressions made upon their consciousness, they presume by something outside it; they know the impressions; they are conscious of them. That which we call ourselves makes answer to something from without, and according to the nature of the answer, the part of our consciousness which responds to the impression, we classify the various external objects, label them and place them in a certain division corresponding to a division in our own consciousness. We find, for instance, that external objects, producing a certain effect upon the consciousness through the senses, are classified as the phenomena which give the basis for science, and the observations are put aside as dealing with the facts with which science is concerned. We find that another class of impressions from without arouses in us what we call feeling, a feeling of pleasure or of pain and so of attraction or repulsion, and that these gradually develop into what we know as emotions; we place them in their own category in turn and realise the emotional nature that responds in us to the impacts giving rise to those feelings and emotions. Then we find that  another set of impressions appeals to a different part of our consciousness and we have what we call thoughts, ideas. Percepts derived through the senses become gradually manipulated by our consciousness into thoughts, ideas, concepts, and we put them into a class by themselves. So we have three classes of impressions - the sensuous, the emotional, the mental, - and these we realise as the answers of our consciousness to certain classes of impressions made upon us by the external world.
Then we begin to ask: is this all? do these three classes include everything to which consciousness responds? is there any other part of our consciousness which does not belong to the body, or the emotions, or the mind, which will respond to certain impressions from without, a class of impressions that cannot be included in one of the three that I have named, and yet impressions that we recognise, and to which we find our consciousness respond? Hence, when the question is asked: have we exhausted all impressions in the sensuous, the emotional, the mental? The normal consciousness of humanity in all times, in all countries, in all stages of civilisation answers distinctly: No; there is something more.
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