In this article I would like to bring the findings of my somewhat unusual but
increasingly accepted field ? mysticism? to the discussion, for I think they
may offer some helpful insights about consciousness. Why? When a biologist seeks
to understand a complex phenomenon, one key strategy is to look to at it in its
simplest form. Probably the most famous is the humble bacterium E. coli. Its
simple gene structure has allowed us to understand much of the gene functioning
of complex species. Similarly many biologists have turned to the ?memory' of
the simple sea slug to understand our own more kaleidoscopic memory. Freud and

Durkheim both used totemism, which they construed as thesimplest form of
religion, to understand the complexities of religious life.1 The methodological
principle is: to understand something complex turn to its simple forms. Mystical
experiences may represent just such a simple form of human consciousness.

Usually our minds are an enormously complex stew of thoughts, feelings,
sensations, wants, snatches of song, pains, drives, daydreams and, of course,
consciousness itself more or less aware of it all. To understand consciousness
in itself, the obvious thing would be to clear away as much of this internal
detritus and noise as possible. It turns out that mystics seem to be doing
precisely that. The technique that most mystics use is some form of meditation
or contemplation. These are procedures that, often by recycling a mental
subroutine,2 systematically reduce mental activity. During meditation, one
begins to slow down the thinking process, and have fewer or less intense
thoughts. One's thoughts become as if more distant, vague, or less
preoccupying; one stops paying as much attention to bodily sensations; one has
fewer or less intense fantasies and daydreams. Thus by reducing the intensity or
compelling quality of outward perception and inward thoughts, one may come to a
time of greater stillness. Ultimately one may become utterly silent inside, as
though in a gap between thoughts, where one becomes completely perception- and
thought-free. One neither thinks nor perceives any mental or sensory content.

Yet, despite this suspension of content, one emerges from such events confident
that one had remained awake inside, fully conscious. This experience, which has
been called the pure consciousness event, or PCE, has been identified in
virtually every tradition. Though PCEs typically happen to any single individual
only occasionally, they are quite regular for some practitioners.3 The pure
consciousness event may be defined as a wakeful but contentless
(non-intentional) consciousness. These PCEs, encounters with consciousness
devoid of intentional content, may be just the least complex encounter with
awareness per se that we students of consciousness seek. The PCE may serve, in
short, as the E coli of consciousness studies.4 But the story does not stop
here. Regular and long-term meditation, according to many traditions, leads to
advanced experiences, known in general as ?enlightenment'. Their
discriminating feature is a deep shift in epistemological structure: the
experienced relationship between the self and one's perceptual objects changes
profoundly. In many people this new structure becomes permanent.5 These
long-term shifts in epistemological structure often take the form of two quantum
leaps in experience; typically they develop sequentially.6 The first is an
experience of a permanent interior stillness, even while engaged in thought and
activity ? one remains aware of one's own awareness while simultaneously
remaining conscious of thoughts, sensations and actions. Because of its
phenomenological dualism ? a heightened cognizance of awareness itself plus a
consciousness of thoughts and objects ? I call it the dualistic mystical state
(DMS). The second shift is described as a perceived unity of one's own
awareness per se with the objects around one, an immediate sense of a
quasi-physical unity between self, objects and other people. States akin to this
have been called ?extrovertive-' or sometimes ?nature-' mysticism; but I
prefer to call it the unitive mystical state, UMS.7 Like the PCE, these latter
two may serve as fertile fields for students of consciousness to plough. To
understand them, I want to introduce the idea of the relative intensity of a
thought or desire. Some desires have a high relative intensity. Let's say I am
walking across the street when I see a huge truck hurtling at me. Virtually 100%
of my attention is taken up with the truck, the fear, and getting out of the
way. It is virtually impossible for me to think about anything else at that
time. I don't even consider keeping my suit clean, how my hair might look, the
discomfort in my tummy, or the classes I will teach tomorrow. The fear and
running are utterly intense, we might say, consuming nearly 100% of my
attention. That