9 Hand and Mind

I have suggested that the hand played an essential role in the origin of language (as have others), but I have not claimed that the hand generates the mind. Those who believe that mind and language are coeval, or even that language is the basis of mind, might make that very strong claim: that the hands are the preexisting form from which mind evolved. I do not find such a view remotely plausible, since I think many animals without hands have minds—such as dogs, cats, and elephants. These animals have paws and hooves, but they don’t have hands. I also accept that reptiles, fish, and even insects have minds, even if of a rudimentary form: so I am not about to suggest that hands are a necessary condition of mindedness. But there is room for a weaker thesis about the human mind in relation to the hand—namely, that the form of our mind is shaped by our handedness. The kind of mind we exemplify is influenced by our possession of hands—hence our specific type of mind evolved from conditions that include our hands. In this chapter I will take a brief synoptic tour of this terrain, without attempting to treat the several topics in any depth. A great deal could be said about each of these topics (and a lot has been said). My aim is just to indicate the many ways that the hand can be seen as shaping the mind, so that we gain a sense of the pervasiveness of the influence. Accordingly, I shall be brisk.

What is most distinctive about human intelligence, as has often been remarked, is that it is a tool-using intelligence. Thus it is creative, teleological, and manipulative. We are inventive creatures; we conceive the world instrumentally; and we confront reality with a view to changing it. We don’t just accept nature as it is; we actively interfere with it. We try to improve on nature, to serve our own ends (often in ways deadly to other species). Large tracts of the material world are thus transformed into human equipment. Other species accept nature as given, with some very minor tinkering, but we engage in wholesale reconstruction. (It is true that some other species are also tool-users, but we have taken this trait to an extreme that far outstrips even the most tool-oriented ape.) We are surrounded by a world of our own making—a world of technology.

The intelligence that makes this world is grounded in the hands, because almost all technology is hand operated: it is designed to fit the anatomy of the hand and the hand’s manipulations control it. We could not have created this world of tools and technology without the hand and its peculiar powers. Our specifically human intelligence has evolved in concert with the hand—so much so that we can speak of “the intelligent hand.” But we also, and equally, have a “handy intelligence.” We express our intelligence in our hands (also in the voice—but language came from the hands originally). What we are particularly intelligent at is figuring out how to make and use hand-operated tools that solve problems.¹

We may conjecture that the hand plays a major role in the growth of individual intelligence, as well as the growth of species intelligence. The child uses her hands to manipulate and explore, acquiring hand skills of many kinds, and without this manual activity intelligence would no doubt be impeded. It is an empirical question to what degree intelligence is affected by hand activity in early years. Those born without hands, or with impaired manual dexterity, might be expected to suffer some intelligence deficit (the same would not be true of the feet). Of course, merely lacking hands does not entail that the parts of the brain dedicated to the hands are also missing or defective, so general intelligence might still be grounded in this. But I would guess that if anyone were born without this part of the brain then intelligence would be severely affected. (I do not know of any studies that provide good data on this question, possibly because that kind of massive but selective brain impairment is very rare and likely to be conflated with other deficits.) A lot of cortex is devoted to the hand, so damage to that part of the brain is bound to have a considerable impact. Lacking even neural programs for manual activity must surely affect intellectual maturation (by contrast, being born without a sense of smell is unlikely to have much of a deleterious effect on general intelligence). When psychologists speak of sensorimotor intelligence, it is primarily the hand they have in mind.²

The hand is also one of the main ways we learn about the world—it is a sensory organ as well as a motor organ. It is hard to believe that this fundamental mode of learning does not shape the way we conceive of things. Our concepts of things will naturally incorporate the way those things are presented to the probing hand. We don’t just have visual and auditory ideas of things; we have manual ideas. A cup, say, is an object that is to be gripped thus-and-so. If we think of perception as incorporating a motor component (as with enactive theories³), then the actions tend to center on the hand; and manual perception feeds into our concepts of the world. Our conceptual scheme is accordingly geared to the human grip (though not only to this). The real is what can be gripped, to put it succinctly; the unreal is what cannot be gripped. Thus our ontological preference is for middle-size dry goods—those we can get our hands on and around. Numbers, minds, and values elude our grip, so we fret about their ontological status. We are instinctive “manual realists”: we believe most firmly in what can be held in our hands.⁴ Other species might be “smell realists” or even “echolocation realists”: the world is what can be smelled or detected by rebounding sounds. We humans interact with the world mainly through our hands, so we tend to favor their take on reality. If we are doubtful about a visual impression, suspecting illusion, we reach out to see if we can grasp the suspected figment. If you have something firmly gripped in your hand, you don’t doubt its existence. The hands are hard to fool—there are not many manual illusions (compared to visual illusions).⁵ Thus human conception and human prehension go, as it were, hand in hand. What would it be like to hold a round square? Ghosts cannot be grasped. Those elusive quanta seem hard to get a grip on. Epigrammatically: the human hand is the measure of all things, so far as human ontology is concerned.⁶

Then there are the archetypal ten digits. It doesn’t take much ingenuity to see a link between arithmetic and human fingers. We count on our fingers; we use base 10; fingers and numbers are both called “digits.” Our elementary mathematical thinking is surely influenced by the structure of our hands. Perhaps in the dim, distant intellectual past it was the hands that gave rise to mathematical ideas. And not just arithmetic, but also geometry: the closed figures—triangles, rectangles, and circles—that can be formed with the fingers, as well the lines on the hands, and the ability of the index finger to trace shapes in external substances like mud or sand. This influence may go beyond arithmetic and geometry and extend to our digital mode of intelligence: we tend to conceive things in tidy discrete units that combine to form wholes—particles, words, and quantities of all kinds. Is this a reflection of our digital hand anatomy? Did we learn this mode of thinking from our hands? A species centered on smell may approach the world in a more analog fashion, because smells are not discrete combinable units. But we apprehend things via the discrete articulated structure of our hands—thus we tend to think digitally. Ten seems to us like an especially distinguished number, the most “natural” of natural numbers. And we like to think in terms of finite combinations of neatly bounded entities that work harmoniously together. The digital hands are our model and paradigm. If you are a snake or a jellyfish, your take on things will be different: perhaps the world will seem more amorphous or seamless—more like you. The mind of a dog, say, will likely reflect its jaws—the teeth will be the dog’s conceptual template or point of ontological reference. The world will be the bite-able world, with a basically binary structure (corresponding to the upper and lower jaw: here I venture into the canine Weltanschauung).⁷

Phenomenology and intentionality will thus reflect the anatomical and physiological properties of a species—how could they not? So there will be variation in the general form of an animal’s mind, according to its bodily makeup: phenomenology reflects phenotype. In humans the hands are vital to our interactions with things, so their form is likely to shape how we mentally represent things. One’s own body is the paradigm physical object, the primary reality, so everything else is apt to be conceived in the light of its peculiarities. An alien made entirely of gases or pure light would have its own distinctive ontological take on the world, quite different from ours. A supernatural being composed entirely of numbers (here we contemplate the counterpossible!) would likely have a different ontological slant again, in which perhaps middle-size physical objects appear as distinctly shady.⁸

I have just explored, all too briefly (and jauntily), some ways in which the mind of man might be shaped by his anatomy, specifically his hand; but there is also the question of whether our concepts of mind might be shaped by our concepts of the hand. Do we conceive of the mind in manual terms? Here the evidence is clear and immediate. Our language is full of prehensive terminology for the mind: “apprehend,” “comprehend,” “grasp,” “be gripped by,” “pick up on,” “hold” (in memory), “catch” (your meaning), “grapple” (with a problem), “reach out” (emotionally), “be seized by” (a passion). Let us take the verb “grasp” as representative of this list; it is common and entrenched. We can be said to grasp a meaning (a sense), to grasp a theory, to grasp an implication—just as we can be said to grasp a doorknob or a tennis racquet. In philosophical jargon, we can be said to grasp “intensional entities” as well as physical objects. Nor is there any sense of outright ambiguity here, as if we just happen to use the same phonetic form for unrelated things. No, the idea is that the two “grasping” relations are significantly similar. We think of the mind as doing to a meaning what the hand does to an object—seizing and grasping it. We model mental grasping on physical grasping—as if a mental hand reaches out (later I will discuss how literally we can take these ways of talking). There is indeed an established philosophical use of “prehend” to describe mental acts like perceiving and thinking. C. D. Broad uses “prehend” in place of Russell’s “acquaintance”: where Russell says that the mind is acquainted with a particular, Broad says that the mind prehends a particular.⁹ The word comes from the Latin prehendere which simply means “to grasp.” The OED gives the following as a definition of “prehension” in philosophical discourse: “an interaction of a subject with an event or entity which involves perception but not necessarily cognition.” This fails to capture the active nature of prehension: the mind “takes hold” of the object, grasping it—it acts on the object. This is a quite different conception from theories that model intentionality on causation: here the object acts on the mind and the mind is passive. But when an object is mentally grasped, it is the mind that is agential. Or perhaps we should say that the person grasps the object (via the mind), to avoid a potential category mistake. The person is the agent of a prehensive mental act, directed toward an object. The naturalness of this way of talking reflects the influence of the hand in shaping how we think about the mind. We grasp the mind as a grasping organ—we apprehend it as apprehensive. Clearly, our psychological concepts are saturated with prehensive imagery.¹⁰

A final point about mind and hand concerns expression. Certain parts of the body are held to express the mind with particular force or directness (not counting speech). Thus the face is taken to express states of mind with special clarity—we speak readily of sad or joyful expressions (frowning, smiling), expressions of surprise, of agreement, of sympathy, and so on. A person’s face can express inner tension or relaxation, according to the disposition of the facial muscles. Not so the back or thorax. But the hands too are highly expressive: hand gestures can be sad or happy, express agreement or sympathy, and show tension or relaxation. Gestures can convey affection or dislike of another. The handshake is particularly expressive. The mind finds a natural outlet in the hands, as a mode of externalization. Our picture of an emotion may be hand based—as with a gesture of resignation or defeat. The raised hand of victory is understood by all. In the pictorial and plastic arts representations of the hands are often highly expressive. We may wonder whether our emotions would be quite the same without hands to express them (as the smile seems so integral to joy or amusement). Thus the emotions of different species may be shaped by the expressive capacities of their bodies: think of the wag of a dog’s tail or a cat’s flattened ears. Obviously, too, the hands are implicated in musical expression and dance, and in expressive writing and painting. The hands are the emissaries of the soul, we might say, as the eyes are the windows. You certainly don’t need hands to have emotions or a soul, but the kind of emotions you have cannot be detached from the kind of body you have. The emotional repertoire of humans, especially the social emotions, has been forged in tandem with the evolution of the characteristics of the human hand. The hands express human emotions, but they also give them their shape.

In conclusion: the hand is not the very origin of mind, to be sure, but it does have important constitutive links to the kind of mind we have evolved. The specific form of the human mind is to a large degree structured by the human hand, by its anatomy and uses. This is not surprising, given that our minds and hands have coevolved over many thousands or millions of years of biological adaptation.¹¹