There is little reason to doubt that in physiological and behavioral terms, secular and religious ecstacy are about the same: the same glands are activated, and the same raw feelings are engaged. What differs is the trigger and the symbolic interpretations used to sustain the state of consciousness and feeling. In mysticism, that interpretation is religious.

Religion is defined as systems that are understood to be, in Frederick Streng's phrase, "means toward ultimate transformation." They also exhibit Joachim Wach's three forms of religious expression: theoretical, practical, and sociological. A religious state, idea, practice (worship), or group must offer a means toward ultimate transformation of self or world or both, and do so through a combination of symbols involving ideas, practices (worship), and interpersonal or group life. It must, to use more common religious terms, offer conversion, salvation, or other means of integrating oneself absolutely into the true nature of the universe (whether God, gods, or subtle forces) and tapping this ultimate's power.

The word religion, then, is useful both philosophically and sociologically because it enables us to isolate the highly visible and immensely important systems of human culture that combine theory, practice, and sociology, and in all these employ symbols of process, absoluteness, and transcendence that indicate the system is intentionally a "means of ultimate transformation."

Mysticism is experience linked to this matrix. It may be regarded as itself the cardinal means toward ultimate transformation; it may be interpreted simply as a contact with the deity or plane that offers it through other means. But in any case, a mystical experience is a state of consciousness whose dominant symbols and structures of thought, behavior, and expression relate to ultimate transformation of self and world, and whose same symbols and stuctures derive from or construct a system with theoretical, practical, and sociological components also pointing toward ultimate transformation. These three Wachian forms need not, of course, be present explicitly in the experience, but they would be implied by the terms, the symbols and structures, through which the mystic experiencer interpreted the experience to himself/herself and others.

Mystical experience is experience in a religious context that is immediately or subsequently interpreted by the experiencer as encounter with ultimate divine reality in a direct nonrational way that engenders a deep sense of unity and of living during the experience on a level of being other than the ordinary.

What then do we really mean by mysticism? A word which is impartially applied to the performance of mediums and the ecstasies of the saints, to "menticulture" and sorcery, dreamy poetry and mediaeval art, to prayer and palmistry, the doctrinal excesses of Gnosticism, and the tepid speculations of the Cambridge Platonists -- even, according to William James, to the higher branches of intoxication -- soon ceases to have any useful meaning. Its employment merely confuses the inexperienced student, who ends with a vague idea that every kind of supersensual theory and practice is somehow "mystical." Hence the need of fixing, if possible, its true characteristics: and restating the fact that Mysticism, in its pure form, is the science of ultimates, the science of union with the Absolute, and nothing else, and that the mystic is the person who attains to this union, not the person who talks about it. Not to know about, but to Be, is the mark of the real initiate.

The difficulty lies in determining the point at which supersensual experience ceases to be merely a practical and interesting extension of sensual experience -- and passes over into that boundless life where Subject and Object, desirous and desired, are one. No sharp line, but rather an infinite series of graduations separate the two states. Hence we must look carefully at all the pilgrims on the road: discover, if we can, the motive of their travels, the maps which they use, the luggage which they take, the end which they attain.

Now we have said that the end which the mystic sets before him is conscious union with a living Absolute. That Divine Dark, that Abyss of the Godhead, of which he sometimes speaks as the goal of his quest, is just this Absolute, the Uncreated Light in which the Universe is bathed, and which -- transcending, as it does, all human powers of expression -- he can only describe to us as dark. But there is -- must be -- contact "in an intelligible where" between every individual self and this Supreme Self, this Ultimate.

We have now, however, to to take account of the fact that often the true mystic is also a mystical philosopher; though there are plenty of mystical philosophers who are not and could never be mystics.

Because it is characteristic of the human self to reflect upon its experience, to use its percepts as material for the construction of a concept, most mystics have made or accepted a theory of their own adventures. Thus we have a mystical philosophy or theology -- the comment of the intellect on the proceedings of spiritual intuition -- running side by side with true or empirical mysticism: classifying its data, criticizing it, explaining it, and translating its vision of the supersensible into symbols which are amenable to dialectic.

Such a philosophy is most usually founded upon the formal creed which the individual mystic accepts. It is characteristic of him that in so far as his transcendental activities are healthy he is generally an acceptor and not a rejector of such creeds. The view which regards the mystic as a spiritual anarchist receives little support from history; which shows us, again and again, the great mystics as faithful sons of the great religions.

Attempts, however, to limit mystical truth -- the direct apprehension of the Divine Substance -- by the formulae of any one religion, are as futile as the attempt to identify a precious metal with the die which converts it into current coin.

From the moment we awake until the moment we fall asleep, the vast majority of us spend our time silently talking to ourselves. A few individuals whom we call mystics have mastered the difficult art of shutting off this habitual interior dialogue. This inner silence that mystics cultivate cannot develop unless the individual first learns how to tightly focus his or her attention so that the mind and imagination no longer wander aimlessly from one subject, thought, or feeling state to another. When this mental background noise ceases as a consequence of the mystic's successful endeavors to focus his or her attention, a dramatic change in the mystic's mode of consciousness takes place, a metamorphosis that is just as radical (sometimes even more so) as that transformation that occurs during the shift from the waking state of awareness to the dream state. This dramatic metamorphosis of the waking consciousness caused by simultaneously focusing the attention and quieting the mind, together with the responses in both thought and deed that it generates, is what I call "mysticism."

It is clear from this description that mysticism incorporates two important elements: a distinctive mode of experience or consciousness and the individual's responses to that unusual modality of experience. It is evident, then, that the term "mysticism" is not synonymous with "mystical experience," for the latter refers only to the first of these two elements. "Mysticism" is instead a comprehensive term incorporating both the mystical experience and the individual's response to it. Because of this dual reference inherent in the term "mysticism," a study of this phenomenon must accomplish two basic tasks. First, it must shed light on those particular attributes that distinguish the mystical mode of consciousness from other modes of consciousness. Second, it must delineate the manifold ways that men and women have responded in both thought and deed to those extraordinary types of experience. In order to accomplish these two tasks, I have divided this study into two parts. Part I, "Mystical Experience: Its Principal Features and Accomplishments," analyzes the peculiarities of the mystical state of consciousness. Part II, "How Tradition Shapes the Mystical Experience and the Mystic's Response To It," focuses more heavily on the nature of the mystics' particular responses to their unusual experiences.