Clark argues that Ballard’s subjects made the pattern of blocks part of their extended mind. It became a store of knowledge they could dip into, an external repository of information. It was as if Inga did not actually recall the address of MOMA but only the page in her notebook where she had written it down. Our memory holds a great deal of information. But the extended mind moves swiftly between outside and inside sources, showing little regard for where its information comes from.
Our minds do more than take in information, of course. They also make decisions and send out commands—and those commands certainly don’t stay inside the mind. In the block-building game, for example, some commands go to neurons in the hand in order to move the computer mouse. But our brains don’t make a perfect mental replica of our hands and the mouse and the table in order to calculate where the mouse needs to go. Our hands and eyes constantly send signals to the brain, and that feedback alters the signals coming back out. Hand, eye, and brain are part of the same system.
We will soon be able to enhance our brains with drugs or implants. But changes we make to the environment already alter our minds.
What’s even more remarkable about our brains is that they actually search for new things to make part of this feedback system. Imagine you are poking a stick into an animal’s burrow. As you poke away, you are aware of what the far end of the stick is touching, not the end you’re holding in your hand. This kind of extended sensation appears to be the result of a reorganization of the brain. Scientists have found that when test monkeys spent five minutes learning how to use a rake, some of the neurons in their hands began behaving in a new way. They began to fire in response to stimuli at the end of the rake, not on the monkey’s hand. Other neurons, in the brain, respond to things that appear to lie within arm’s reach. Training the monkeys to use the rakes caused these neurons to change—reacting to objects lying within rake’s reach rather than arm’s reach.
The eagerness with which the brain merges with tools has made it possible to create some stunning mind-machine interfaces. For instance, Miguel Nicolelis of Duke University and his colleagues put electrodes in the brains of monkeys to link them to a robot arm. The monkeys quickly learned how to move the arm around with pure thought; their neurons reorganized, establishing a new feedback loop between brain and robot arm.
Humans are proving just as good at this merger of mind and machine. The U.S. Navy has developed a flight suit for helicopter pilots that delivers little puffs of air on the side of the pilot’s body as his helicopter tilts in that direction. The pilot responds to the puffs by tilting away from them, and the suit passes those signals on to the helicopter’s steering controls. Pilots who train with this system can learn to fly blindfolded or to carry out complex maneuvers, such as holding the helicopter in a stationary hover. The helicopter becomes, in effect, part of the pilot’s body, linked back to his or her mind.
Results like these, Clark argues, reveal a mind that is constantly seeking to extend itself, to grab on to new tools it has never experienced before and merge with them. Some people may be horrified by how passionately people are taking to their laptops and GPS trackers. But to Clark it would be surprising if we didn’t. We are, in Clark’s words, “natural-born cyborgs.”
The extended mind theory doesn’t just change the way we think about the mind. It also changes how we judge what’s good and bad about today’s mind-altering technologies. There’s nothing unnatural about relying on the Internet—Google and all—for information. After all, we are constantly consulting the world around us like a kind of visual Wikipedia. Nor is there anything bad about our brains’ being altered by these new technologies, any more than there is something bad about a monkey’s brain changing as it learns how to play with a rake.
Neuroscientists will soon be able to offer fresh ways to enhance our brains, whether with drugs or with implants. To say that these are immoral because they defile our true selves—our isolated, distinct minds—is to ignore biology. Our minds already extend out into the environment, and the changes we make to the environment already alter our minds.
That doesn’t mean we must approve of every possible extension of the mind, and even good extensions will have some drawbacks. Socrates worried that writing would make people forgetful and unwise. Sure enough, writing did rob us of some gifts, such as the ability to recite epic poems like The Iliad from memory. But it also created a much larger pool of knowledge from which people could draw, a pool that has continued to expand (or, dare we say, continued to extend?).
There’s no point in trying to hack apart the connections between the inside and the outside of the mind. Instead we ought to focus on managing and improving those connections. For instance, we need more powerful ways to filter the information we get online, so that we don’t get a mass case of distractibility. Some people may fear that trying to fine-tune the brain-Internet connection is an impossible task. But if we’ve learned anything since Clark and Chalmers published “The Extended Mind,” it’s not to underestimate the mind’s ability to adapt to the changing world.
