Degrees of Mind and Body
We are accustomed to a sharp and rigid distinction between mind and body, between “the mental” and “the physical”. We also tend to think that these are absolute concepts: something is either one or the other with no degrees. One thing can’t be more mental than another, or more physical. These categories don’t admit of gradation; there is no sliding scale of mentality or physicality. But is this right? It seems to me that it is just another example of the human tendency to prefer discontinuity over continuity—to be uncomfortable with variations on a theme and happier with simple dichotomies. Actually, the mental and physical (mind and body) do come in degrees and things do vary in their status as mental or physical. This is in fact easy to prove and conceptually quite liberating.
As usual, the dictionary will put us on the right track (there is more philosophical wisdom in a good dictionary than in Kant’s Critique of Pure Reason). For “mental” the OED gives us “relating to, done by, or occurring in the mind”: clearly, that admits of degree. Something could be more or less closely related to the mind, more or less distant from the mind, more or less done by the mind, and partially occurring in the mind. But we need to know what “the mind” is before these linguistic intuitions can be accorded conceptual (ontological) weight. For “mind” the OED has “the faculty of consciousness and thought” and “a person’s ability to think and reason; the intellect”. This is commendably definite and quite restrictive: the mind is equated with conscious reason, intellect, thought—not perception, emotion, sensation, or character. These things are thus not deemed “mental”, since they are not done by, or occur in, the intellect. Memory is not included, but we can suppose it closer to the mind, as so defined, than sense perception and bodily sensation. Character traits are quite far from the mind (intellect) and are therefore only weakly mental; perception and sensation more strongly so, emotion more strongly still, memory almost there. We have grades of mentality—a sliding scale. In humans, thoughts about thoughts, the intellect directed onto itself, might qualify as the most strongly mental; sensations in the bowel as the most weakly mental. It all depends on proximity to the intellect—similarity to what the intellect is or does. Thus, mentality comes in degrees—some things are more mental than others.
The story with “physical” is very similar. The OED gives us “relating to the body as opposed to the mind”, citing the phrase “a physical relationship”. Again, that can intuitively admit of degrees—things can be more less related to the body, more or less connected to it, or like it. But we need to know more about what exactly the body is before we can have a definite idea of what “physical” means. The dictionary obliges us with “the physical structure, including the bones, flesh, and organs, of a person or animal”, adding as “technical” “a material object”. Clearly, things can be more or less similar to a body as so defined: trees, rocks, liquid water, clouds, volumes of air, regions of space. Some things are more body-like than others in the animal-body sense. Thus, some things are more “physical” than others—trees more than clouds. What about the technical sense? Here we need to move a bit towards physics itself. A material object is understood to be a discrete bounded solid thing located in three-dimensional space—as opposed to such things as heat, light, radiation, gravity, magnetism, and fields of force. It used, indeed, to be debated whether such items were really physical at all, given the paradigm supplied by the material object. Such debates presuppose a dichotomous attitude to nature—isn’t it better to say that physicality comes in degrees? Some things are more like material objects than others—with neutrinos and force fields at some distance from the paradigm (electrons and protons closer). Thus, physicality comes in degrees. Black holes (misnamed—they aren’t holes in anything) are frightfully physical, being of enormous mass and density, stars somewhat less so, oceans still less, air even less, empty space hardly physical at all. It is pointless to try to force some sort of dichotomy onto this sliding scale; better just to speak of degrees of physicality (body-hood). This spares us pointless verbal quibbles and pseudo-questions. The dichotomous use of “physical” belongs to an earlier stage of physics, i.e., Cartesian mechanism (the dichotomous use of “mental” is similarly rooted in the past, mainly religious, i.e., incorporeal soul versus material substance).
It would be nice if the two scales overlapped—if one graded smoothly into the other. Could the least physical thing also be the least mental? Could there be a borderline case? I think this has been supposed by some very free thinkers: thus, we hear talk of “energy fields” that are vaguely spiritual, light is supposed to be mindlike, the impalpably physical has been likened to the soul. Ghosts, if such there be, are thought to hover on the boundary between the mental and the physical. This would be intriguing if true, because it might give us a handle on the mind-body problem; but alas, it is just loose talk, metaphor, misty poetry. There is really nothing that qualifies as genuinely both mental and physical—though some things combine the two. Nothing is both like the animal body and also like the intellect—both flesh and bone and also thought and reason. True, actions can be described physically and mentally—as material movements of the body and as intentional. But this is because they are double-aspect things: the aspects are not midway between the mental and the physical. The movement isn’t like a thought and the intention isn’t like a limb. Still, this supposed middle ground is worth pondering as a conceptual possibility, because it offers the prospect of psychophysical linkage—intelligible emergence. There could perhaps be something, now unknown, that straddles the divide, something close enough to both paradigms. Anything like the intellect and also like the animal body would be a candidate for being the key to unlocking the mind-body problem.[1]
[1] One result of adopting a degree conception of the mental and physical is that we get different strengths of materialism. Suppose the conscious intellect were reducible to the gross anatomy of the brain: that would be an extremely strong form of materialism, because it would take the paradigm of the mental and reduce it to the paradigm of the physical. The strongly mental would reduce to the strongly material (I don’t think anyone has ever championed such a view). By contrast, it might be claimed that memory or unconscious belief is reducible to electrical properties of neurons—these both being relatively weak instances of the mental and physical. Or again, it might be held that character traits consist of energy fields (unknown to current physics) surrounding the pineal gland—where these are understood as quite remote from the usual paradigms. In other words, we can envisage different degrees of materialism, depending on what mental and physical phenomena we are considering.
