Of course, unlike the T-101, who doesn’t even flinch when a cigar is ground out on his beefy chest, this poor biker can actually feel the scorching of his soft tissue. Nonetheless, his conscious awareness of this pain isn’t what agitates his limbs and causes the air to stream from his lungs in a tortured howl, at least not according to Descartes. The real cause of these motions can be traced back to the operation of what he (somewhat misleadingly) called “animal spirits” that flow through the nerves to particular locations in the body and cause certain muscles to contract or expand. When you read the phrase “animal spirits,” banish the image of microscopic gremlins and picture instead tiny particles of matter resembling “a certain very fine air or wind”
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that stream in one direction or another in response to external objects that strike our nerve endings. Nowadays, neuroscience has jettisoned “animal spirits” and replaced them with electrochemical impulses, but it’s still basically the same idea. This is why Descartes’ pioneering attempt to identify and explain the mechanism behind involuntary or automatic physical reactions, however handicapped by his century’s primitive understanding of physiology, makes him a major figure in the development of reflex theory.
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But how far can we take this? How much of what we do can be adequately explained using the same “billiard ball” model that allows us to predict the exact arc of someone thrown across a bar? And how long before this attempt is stymied by the discovery that there are some actions that can’t be explained without taking account of thought and feeling, which are not material? Descartes’ answer is that the “billiard ball” model can take us a lot further than you might expect. For nonhuman animals, at least, he believed there was nothing they did that required us to assume they were conscious. He was convinced that
all
their actions—eating, hunting, mating, you name it—obeyed the same mechanical necessity as the automatic reflex that causes Dr. Silberman’s face to contort into a grimace when Sarah Connor wallops his arm with a nightstick, breaking one of the “two hundred and fifteen bones in the human body.”
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Centuries before the term “cybernetics” had even been coined, Descartes’ idea of the
bête-machine
or “Beast-Machine” dared to erase the difference between biological and mechanical things. He denied that there’s any essential difference between animal bodies and “clocks, artificial fountains, mills, and similar machines which, though made entirely by man, lack not the power to move, of themselves, in various ways.”
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Many of Descartes’ contemporaries, however, balked at this idea. One of those skeptics was Antoine Arnauld (1612-1694), who expressed his reservations concerning the
bête-machine
in this way:
It appears incredible how it could happen, without the intervention of any soul, that light reflected from the body of a wolf onto the eyes of a sheep should move the extremely thin fibers of the optic nerves, and that, as a result of this motion penetrating into the brain, animal spirits [“electrochemical impulses”] are diffused into the nerves in just the way required to cause the sheep to take flight.
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We’ll have more to say shortly about Arnauld’s reference to the animal “soul.” For now let’s just note the similarity between Descartes’ explanation of how light reflected from the wolf sets the sheep’s limbs in motion and what we might suppose happens inside a Terminator when light bearing the image of John Connor strikes its optical sensors. The only difference is that the Terminator’s limbs are stirred to attack, not flee.
Descartes responded to Arnauld’s criticisms with a reminder of how many of our own actions, such as shielding our heads with our arms when we fall, are carried out mechanically, without any conscious exercise of mind or will. But what persuaded him that
everything
an animal does is just as mechanical as those automatic reflexes? And if animals are machines, where, if
anywhere
, do the mechanistic worldview and mechanistic explanation find their limits?
The Thing That Separates Us from the Machines
In the premiere episode of the second season of
Terminator: The Sarah Connor Chronicles
(“Samson & Delilah”), we’re introduced to Catherine Weaver, the icily beautiful CEO of high-tech ZieraCorp, whose elegant comportment, somehow both fluid and robotic, coupled with her disconcertingly intense interpersonal style, alerts us that she may not be exactly what she seems. Our suspicions are confirmed at the episode’s end, when she skewers a disgruntled employee through the forehead with a metallic baton that grows from her finger. In an earlier scene, Weaver directs her gaze out the huge picture window of her high-rise office onto the streets and sidewalks below and comments on the throngs of people who course along these public arteries: “They flow from street to street at a particular speed and in a particular direction, walk the block, wait for the signal, cross at the light, over and over, so orderly. All day I can watch them and know with a great deal of certainty what they’ll do at any given moment.” Contemplated from the Olympian heights of an executive suite, the flow of human crowds seems as orderly and predictable as the “animal spirits” that dart through the nerves of Descartes’
bête-machine
. Still, observes Weaver, human beings aren’t machines, something she believes is very much to our disadvantage.
Weaver’s speech recalls a famous passage from Descartes’
Meditations on First Philosophy
, in which the philosopher reflects that “were I perchance to look out my window and observe men crossing the square, I would ordinarily say that I see the men themselves. . . . But what do I see aside from hats and clothes, which could conceal automata? Yet I judge them to be men.”
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For Weaver, the pedestrian traffic she views from her window resembles the orderly workings of a machine. By the same token, Descartes peers out his window at what for all he knows could be machines in disguise. How can he be sure they’re not
bête-machines
—apes or bears walking upright, decked out in human apparel—or maybe even
humanoid-machines
, early prototypes of the T-101? This possibility feeds our suspicion that even if we made the imposters doff their hats and other garments, we might still have trouble deciding whether they’re machines, since the human tissue under their clothes might also be part of the charade.
The lesson here, according to Descartes, is that we can’t judge whether something is a machine on the basis of superficial appearances, as he believes most people do when they take animals to be more than mere automata. As he wrote to one of his many correspondents:
Most of the actions of animals resemble ours, and throughout our lives this has given us many occasions to judge that they act by an interior principle like the one within ourselves, that is to say, by means of a soul which has feelings and passions like ours. All of us are deeply imbued of this opinion by nature.
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From the outward conduct of certain animals, we begin to believe in the presence of an “interior principle,” something that operates in a manner entirely different from billiard balls, cogs, and gears. While these things obey laws of motion, the “interior principle,” which Descartes calls the “soul,” moves the body from within, guided by a conscious awareness (“feelings”) of what’s happening around it and a will (“passions”) to persist in existence and achieve some degree of well-being.
Most of Descartes’ contemporaries took it as a given that every animal had some sort of soul, although they denied that any nonhuman animal had a
rational soul
. In believing this, they were following in footsteps of the Greek philosopher Aristotle (384-322 BCE) as well as being good Christians, since they claimed that our rational souls made members of our species uniquely eligible for a heavenly existence in the glorious hereafter. Still, observing the care animals take for their survival and well-being, most thoughtful people found it hard to shake the impression that there must be
something
in there, something at least
analogous
to a human soul, elevating even the lowliest beast above the mindless matter of an automaton. But what seemed obvious to most people seemed to Descartes like a prejudice born of a failure to appreciate how well the whole gamut of animal behavior might someday be explained through mechanistic principles without ascribing to animals any awareness or will (or so, at least, he believed). In the meantime, though, he thought it was crucially important to identify correctly the signs of the soul’s presence, for otherwise we end up fudging the line that separates ensouled beings from mere machines.
In her voice-over narration at the beginning of the
SCC
episode “The Demon Hand,” Sarah Connor also refers to “the soul” as “the thing that separates us from the machines.” For both Sarah and Descartes, having a soul doesn’t
necessarily
imply that there’s some mysterious part of us that literally survives the death of the body, active and alert in its postmortem existence. “Gone is gone,” says Sarah in that same voice-over, making her position on the matter perfectly clear. When asked by Cameron (not James Cameron, but the female Terminator of that name played by Summer Glau) whether she believes in the Resurrection, Sarah scoffs and replies that faith is no more a part of her “programming” than it is of Cameron’s (
SCC
, “Samson and Delilah”).
Descartes, on the other hand, goes so far as to argue that it’s at least possible for the soul to survive apart from the body. But he’s quick to add that personal immortality might be the sort of thing that requires God’s active cooperation, something about which he declines to speculate further. Whether faith was part of
his
programming we may never know for sure.
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But the important thing about the soul for both of them is that it serves as a kind of bulwark against our total subjection to the machines. For Sarah, the soul is the locus of our endangered humanity, threatened both by Skynet and, no less, by the sacrifices and moral compromises that are part and parcel of the fight against Skynet. For Descartes, the soul represents the limit of mechanistic explanation, since he insists there are things human beings can do by virtue of having souls that lie outside the capacity of any possible machine. For both Sarah and Descartes, the soul is something intangible that we discern only on the basis of certain outward signs, although they part company as to what those signs are.
Descartes offered us a little sci-fi fable as a way to overcome an obstacle that he believed prevented many people from accepting his doctrine of the
bête-machine
, the force of
habit
. Our belief that animals have souls has been ingrained in us by a lifetime of making, and acting upon, that judgment. To get past this, he invited one of his correspondents to consider someone whose childhood experiences were very different from ours. Although Descartes didn’t give this child a name, let’s call him Danny Dyson and make him the son of Dr. Miles Bennett Dyson.
The child in Descartes’ fable has been raised in a workshop, surrounded since birth with the most ingenious man-made automata imaginable. So let’s imagine our Danny growing up at a time when the project of reverse-engineering the T-101 from its recovered remains is well under way, since in our story the Connors never tossed those remains into a vat of molten metal or blew the Cyberdyne lab to smithereens. Let’s also imagine that Danny had never ventured outside the Cyberdyne Systems compound, so that, as Descartes puts it,
he had never seen any animals except men; and suppose he was very devoted to the study of mechanics, and had made or had helped to make, various automatons shaped like a man, a horse, a dog, a bird, and so on, which walked and ate, and breathed, and so far as possible imitated all the other actions of the animals they resembled including the signs we use to express our passions, like crying when struck and running away when subjected to a loud noise.
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Descartes’ scenario meshes with the
Terminator
saga remarkably well, except for the little detail about crying, since we learn in
Terminator 2: Judgment Day
that Terminators (who are, after all, big boys) don’t cry. But dry-eyed androids aside, we can’t help but marvel at this seventeenth-century philosopher’s dream of “mechanics” progressing to the point where we can construct “machines having the organs and shape of a monkey or of some other animal lacking reason,” simulating them so perfectly that “we would have no way of knowing they were not of the same nature as these animals.”
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Continuing our slightly embellished version of Descartes’ story, would Danny, having been raised alongside both “real men” and reverse-engineered T-101s with “only the shape of men,” find it equally impossible to tell
them
apart? Certainly not, says Descartes. For “if there were any such machines that bore a resemblance to our bodies and imitated our actions as far as this is practicably feasible, we would always have two very certain means of recognizing that they were not at all, for that reason, true men.”
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We’ll describe those means in a moment. But, to cut to the chase, Descartes predicts that should Danny ever come across real animals, as opposed to the Cyberdyne
bête-machines
he grew up with, he’ll discover that they lack the same features that distinguish human beings from machines, forcing him to conclude that biological animals, no less than the synthetic variety, “were automatons, which, being made by nature, were incomparably more accomplished than any of those he had previously made himself.”
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