Since this book first appeared, nineteen years ago, the study of mysticism--not only in England, but also in France, Germany and Italy--has been almost completely transformed. From being regarded, whether critically or favourably, as a byway of religion, it is now more and more generally accepted by theologians, philosophers and psychologists, as representing in its intensive form the essential religious experience of man. The labours of a generation of religious psychologists--following, and to some extent superseding the pioneer work of William James--have already done much to disentangle its substance from the psycho-physical accidents which often accompany mystical apprehension. Whilst we are less eager than our predecessors to dismiss all accounts of abnormal experience as the fruit of superstition or disease, no responsible student now identifies the mystic and the ecstatic; or looks upon visionary and other "extraordinary phenomena" as either guaranteeing or discrediting the witness of the mystical saints. Even the remorseless explorations and destructive criticisms of the psycho-analytic school are now seen to have effected a useful work; throwing into relief the genuine spiritual activities of the psyche, while explaining in a naturalistic sense some of their less fortunate psycho-physical accompaniments. The philosophic and theological landscape also, with its increasing emphasis on Transcendence, its new friendliness to the concept of the Supernatural, is becoming ever more favourable to the metaphysical claims of the mystics. On one hand the prompt welcome given to the work of Rudolf Otto and Karl Barth, on the other the renewed interest in Thomist philosophy, seem to indicate a growing recognition of the distinctness and independence of the Spiritual Order. and a revival of the creaturely sense, strongly contrasting with the temper of late nineteenth-century thought.
Were I, then, now planning this book for the first time, its arguments would be differently stated. More emphasis would be given (a) to the concrete, richly living yet unchanging character of the Reality over against the mystic, as the first term, cause and incentive of his experience; (b) to that paradox of utter contrast yet profound relation between the Creator and the creature, God and the soul, which makes possible his development; (c) to the predominant part played in that development by the free and prevenient action of the Supernatural--in theological language, by "grace"--as against all merely evolutionary or emergent theories of spiritual transcendence. I feel more and more that no psychological or evolutionary treatment of man's spiritual history can be adequate which ignores the element of "given-ness" in all genuine mystical knowledge. Though the mystic Life means organic growth, its first term must be sought in ontology; in the Vision of the Principle, as St. Gregory the Great taught long ago. For the real sanction of that life does not inhere in the fugitive experiences or even the transformed personality of the subject; but in the metaphysical Object which that subject apprehends.
Again, it now seems to me that a critical realism, which found room for the duality of our full human experience--the Eternal and the Successive, supernatural and natural reality--would provide a better philosophic background to the experience of the mystics than the vitalism which appeared, twenty years ago, to offer so promising a way of escape from scientific determinism. Determinism--more and more abandoned by its old friends the physicists--is no longer the chief enemy to such a spiritual interpretation of life as is required by the experience of the mystics. It is rather a naturalistic monism, a shallow doctrine of immanence unbalanced by any adequate sense of transcendence, which now threatens to re-model theology in a sense which leaves no room for the noblest and purest reaches of the spiritual life.