Mind and Body are Mutually Independent
by Peter Meyer
Written May 28, 2013, revised June 11, 2013

As is well-known a dualism of mind (thinking substance) and body (extended substance) was proposed by René Descartes in his Principia philosophiae (published in 1644), and became the basis of what is today known as the philosophical problem of the relation of mind to body.  Descartes’ dualism has been criticized by many philosophers. There are reasons to hold that it is mistaken (or at least a gross oversimplification), but in this essay that dualism is accepted (for the sake of argument) with the following clarifications:

Mind is synonymous with consciousness, which itself needs no definition because we all know it directly.  Much can be said about it, but it is indefinable and inexplicable, except insofar as neural correlates of consciousness can be ascertained by empirical experiment.  (These neural correlates are identified with consciousness by so-called Identity Theorists, a view which is erroneous but whose criticism need not detain us here.)

Body is synonymous with physical object, but in this context it means an organized system of closely-connected physical entities (molecules, tissues, etc., and non-biological systems such as computers) functioning in ways which may or may not be entirely understood (which is certainly the case for all biological organisms).

We are, of course, most familiar with the connection between mind and body in the case of our own minds and bodies.  Normally our mind is intimately connected with our body.  The connection is so close that some philosophers identify them (erroneously).  For example, a normal person needs only to will their arm to rise and it rises (although what, upon examination, the will is, or even if there is such a thing at all, is not entirely clear).  We appear to ourselves as bodies (somehow) conscious among many other bodies (organic and inorganic) comprising the physical world, that is, the world which we experience and know by means of our outer senses (mainly sight and touch, augmented by taste and smell).

When the biochemistry of the brain is altered by the introduction of certain chemical substances, this normal experience of an intimately-connected body and mind may be altered, in some cases very much so.  These chemical substances are among those classified as psychedelics, among which are the well-known LSD, psilocybin and mescaline, and the less well-known DMT, ketamine, ibogaine, 2C-B, etc. 

Most philosophers of mind pay little or no attention to the known effects of psychedelics upon consciousness.  This may be explained by the effects of the so-called War on Drugs (promoted principally by the U.S. and to a lesser extent by other countries following its lead).  It may be that some (most?) philosophers are reluctant to discuss (in public) the well-known (although extremely diverse) effects of LSD and other psychedelics on consciousness because these substances are illegal and proscribed, and they do not wish to be seen as possibly condoning what is illegal. Or it may be that they are simply afraid to venture beyond normal consciousness. Whatever, the fact is that consciousness is consciousness in all its forms, not just in its normal form, that is, everyday consciousness, the sort you are aware of when on the job or eating dinner (when not under the influence of drugs such as alcohol and nicotine).  So philosophers who ignore forms of consciousness induced by the ingestion of psychedelics (either as personal experience or as reports by others) ignore a vast realm of empirical data which is very relevant to their implicitly stated intention to attempt to understand consciousness.

There are a large (and increasing) number of known psychedelics, and they have a huge diversity of effects upon the mind.  Of particular interest are those which induce (to some degree) a separation of mind and body.  These have been classified as dissociatives, the most well-known being ketamine, but there are others which may or may not be classified as dissociatives, in particular, DMT.  The effects of these, which we may call separative psychedelics, are well-documented in the psychedelic literature, which any philosopher may read if they care to (see especially the many trip reports at Erowid). DMT is an especially interesting substance, since it can induce complete loss of bodily awareness and its replacement by what appears as a totally alien dimension of consciousness.

As noted above, in normal consciousness (human and presumably animal consciousness)  there is a very intimate relation between mind and body.  Under the influence of a separative psychedelic such as ketamine, awareness of the body is greatly lessened, and in its place there is awareness of something hard to describe but which is directly known to anyone who has used such a substance.  Intriguing (sometimes overwhelming) visual imagery is common (often complex, and which may change rapidly or slowly), normal concepts of space and time may be severely altered, strange and sometimes profound ideas may enter the mind, and there may even be an awareness (vague or clear) of other (‘higher’) intelligent entities, with whom communication may be attempted (if not wholly successfully).

Under the influence of a separative psychedelic it is not uncommon to come to believe that one is dying, or is about to die. (There may even be a 'realistic' awareness of undergoing some kind of orderly transition to a post-mortal state.)  This, of course, may lead to considerable anxiety.  The reason for this anxiety is based upon our usual understanding of death, which we have formed from seeing or hearing about dead bodies.  When a person dies, their body, which previously was an expression of their mind, with all its displays of emotion, intelligence (or lack of it), intention, relation to others, etc., ceases to be an expression of their mind, and becomes inert: the soul has fled.  If one loved that person then this is often a traumatic experience.  In any case, the event is not understood, and is usually feared.

When we witness the death of a person (although in modern Western society, wherein death is taboo, this rarely happens, though much simulated or fictional 'death' is shown to us from childhood via television) we see that the body suddenly ceases to function.  Under the influence of a separative psychedelic we lose (partially or wholly) awareness of our functioning body.  Our body continues to function normally (unless the chemical interferes with the biological functions needed to sustain life), it’s just that we no longer are intimately connected to it.  This absence of awareness leads us to believe that our body itself has ceased functioning, which is death, and so the fear associated with death arises in our mind.  A person who has had much experience with separative psychedelics may learn to control this fear, based on their knowledge that in past experiences of this sort they have never died, but have always eventually returned to normal consciousness (although there is always the lingering doubt: but this time?).

Even though awareness of the body may have (largely) disappeared, there remains awareness of something which is not the body (as said above, hard to describe).  This shows that body-awareness does not constitute the whole of possible consciousness.  I suggest that the extent of  non-body-awareness consciousness may be as great as the extent of our consciousness of the physical world, and that there is an oneiric world which may be as vast as the physical world (although as yet largely undiscovered, and certainly undiscovered by most people).  The term oneiric relates to dreams, but I suggest that this is an appropriate term for this (largely undiscovered) world because most people’s experience of the oneiric world is confined to their dreams.  But beyond dreaming are states of consciousness similar in nature but very different. Dreaming is like wading in the shallows at the seashore, and being conscious under the influence of a powerful psychedelic is like going way out and diving into the depths; but there's no essential difference between the shallows and the depths. Our personal selves lie at the intersection of these two worlds, the physical and the oneiric, and we can experience both, sometimes at the same time.

As regards the title of this essay, it may be objected that the mind depends on the body, in the sense that without a functioning body (with, in the case of humans, a functioning brain) there can be no mind (no consciousness connected with that body).  This is simply a dogmatic assertion made by those philosophers who hold (erroneously) that only what is physical really exists (from which false assumption they draw the false conclusion that consciousness must somehow be something physical).  There is no convincing evidence to support this assertion; it is rather an act of faith.  The existence of neural activity which is correlated with some mental content does not prove identity, and those who emphasize this correlation ignore the much larger amount of (potential and reported) mental content which has no known (or even any plausibly likely) correlation with neural activity. Evidence which refutes the assertion of the dependence of mind on body is (as pointed out above) provided by the huge number of reports of psychedelic experience, especially that experience under the influence of separative psychedelics, wherein consciousness of the body may be lost but consciousness remains, and may be extremely rich in content.  Thus the available evidence supports the claim that mind is not dependent on body.

And, of course, body is not dependent on mind.  A computer is an organized system of closely-connected physical entities (atoms, molecules, crystals, gates, circuits, magnetic or other memory, etc.) but there is no mind connected with it.  (This is true also of any imaginable computer, because whatever can be assembled from parts cannot be a conscious being, since when, during the process of assembly, would consciousness arise?)  Thus the title of this essay: Mind and body are mutually independent.


"Though the present condition of man be earthly, made of the earth, feeds on the earth, and is dissolved to the earth, and therefore the soul doth less discover herself by her proper actions than doth the material body; yet it is not unknown to philosophy that there is an ecstasis of the soul, wherein she is carried in a trance, wholly and only intending the intellectual functions, while the body lies dead like a carcass, without breath sense motion or nourishment, only as a pledge to assure us of the soul's return." — Christopher Goodman, Fall of Man (1616)


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