We must believe in free will. We have no choice.
– Isaac Bashevis Singer
What Kind of Computer Is the Brain?
Computers can’t do everything humans do—not yet, anyway—but they’re gaining on us. Some believe that, within this century, human intelligence will be seen as a remarkable, but nonetheless primitive, form of machine intelligence. Put the other way round, it’s likely that we will learn how to build machines that do everything we do—even create and emote. As computer pioneer Danny Hillis famously put it, “I want to build a machine who is proud of me.”
The revolutions wrought by the Copernican and Darwinian models shook us because they were seen as an attack on our status. Without proper preparation, the general public may experience the advent of sophisticated thinking machines as an insult to human pride and throw a tantrum that dwarfs all prior reactionary behavior.
At the present time, there are many candidate models of brain function, but none is so accurate and complete as to subsume all the others. Until the brain is understood as well as the other organs that sustain life, a new sense of self will co-exist with the old.
The computer pioneer John von Neumann expressed the difference between the machines we build and the brains we’ve got by dubbing them “serial” and “parallel” computers, respectively. The principal difference between serial and parallel computers is that the former carry out one command after another, sequentially, while in the latter thousands of processes go on at once, side by side, influencing one another. Every interaction—whether with the world, with other individuals, or with parts of itself—rewires the menome. The brain that responds to the next input differs, at least slightly, from the one that responded to the last one. When we understand how brains work well enough to build better ones, the changes to our sense of self will swamp those of prior intellectual revolutions.
The genome that characterizes a species emerges via a long, slow Darwinian process of natural selection. The menomes that characterize individuals also originate via a Darwinian process, but the selection is among neural circuits and occurs much more rapidly than the natural selection that drives speciation. That the brain can be understood as a self-configuring Darwinian machine, albeit one that generates outcomes in fractions of a second instead of centuries, was first appreciated in the 1950s by Peter Putnam. Though the time constants differ by orders of magnitude, Putnam’s functional model of the nervous system recognized that the essential Darwinian functions of random variation and natural selection are mirrored in the brain in processes that he called random search and relative dominance.
In 1949, Donald O. Hebb enunciated what is now known as the “Hebb Postulate,” which states that “When an axon of cell A excites a cell B and repeatedly and persistently takes part in firing it, some growth process or chemical change occurs in one or both cells such that A’s efficiency in firing B is increased.” Peter Putnam’s “Neural Conditioned Reflex Principle” is an alternative statement of Hebb’s postulate, and involves an expansion of it to include the establishment and strengthening of inhibitory or negative facilitations, as well as the excitatory or positive correlations encompassed in the Hebb Postulate. The Hebb-Putnam postulate can be summed up as “Neurons that fire together wire together.”
The reason replicating, or even simulating, brain function sounds like science fiction is that we’re used to relatively simple machines—clocks, cars, washing machines, and serial computers. But, just as certain complex, extended molecules exhibit properties that we call life, so sufficiently complexity and plasticity is likely to endow neural networks with properties essentially indistinguishable from the consciousness, thought, and volition that we regard as integral to selfhood.
We shouldn’t sell machines short just because the only ones we’ve been able to build to date are “simple-minded.” When machines are as complex as our brains, and work according to the same principles, they’re very likely to be as awe-inspiring as we are, notwithstanding the fact that it will be we who’ve built them.
Who isn’t awed by the Hubble telescope or the Large Hadron Collider at CERN? These, too, are “just” machines, and they’re not even machines who think. (Here I revert to who-language. The point is that who or what-language works equally well. What is uncalled for is reserving who-language for humans and casting aspersions on other animals and machines as mere “whats.” With each passing decade, that distinction will fade.
The answer to “Who am I?” at the dawn of the age of smart machines is that, for the time being, we ourselves are the best model-building machines extant. The counter-intuitive realization that the difference between us and the machines we build is a bridgeable one has been long in coming, and we owe it to the clear-sighted tough love of many pioneers, including La Mettrie, David Hume, Mark Twain, John von Neumann, Donald Hebb, Peter Putnam, Douglas Hofstadter, Pierre Baldi, Susan Blackmore, David Eagleman, and a growing corps of neuroscientists.
Yes, it’s not yet possible to build a machine that exhibits what we loosely refer to as “consciousness,” but, prior to the discovery of the genetic code, no one could imagine cellular protein factories assembling every species on the tree of life, including one species—Homo sapiens—that would explain the tree itself.
The Self Is Dead. Long Live the Superself.
The generalization of the self-concept to the superself is unlikely to receive a reception much different from that accorded Twain’s What Is Man?.
The co-creation characteristic of the superself will be scorned as collectivism, if not socialism. Reciprocal dignity will be ridiculed as utopian. Asking “What am I?” instead of “Who am I?” will be dismissed as reductive, mechanistic, and heartless.
Although the superself incorporates the witness, and so has a religious provenance, it’s fair to ask if it will ever speak to the heart as traditional religious models have done. It’s not easy coming to terms with life as a property of inanimate matter, arranged just so, and it will likely be even more difficult to accept ourselves as extended, self-conscious, willful machines.
Many will feel that this outlook is arid and bleak, and want to know: Where’s the mystery? How about love? Doesn’t this mean that free will is an illusion? Awe and wonder and the occasional “Eureka!” may be enough for science, but religious models have offered fellowship, absolution, forgiveness, salvation, and enlightenment. People of faith will want to know what’s holy in this brave new world.
The perspectives of religion and science on selfhood, though different, are not incompatible. Without oversimplifying or mystifying either, it’s possible to identify common ground, and, going forward, a role for both traditions. I propose such a collaboration in Religion and Science: A Beautiful Friendship?.
My guess is that once we’re in the presence of machines that can do what we do the model of selfhood we’ll settle on will be even more fecund than the traditional one. That co-agency replaces individual volition will not undermine a sense of purpose, though it will require a redefinition of personal responsibility. There’s no reason to think that machines that are sophisticated enough to outperform us will evoke less wonder and reverence than organisms that have arisen via natural selection. Mystery does not attach itself exclusively to human beings. Rather, it inheres in the non-human as well as the human, in the inanimate as well as the animate. As Rabbi Abraham Heschel notes, “Awe is an intuition of the dignity of all things, a realization that things not only are what they are but also stand, however remotely, for something supreme.”
Contrary to our fears, the capacity of superselves for love, fellowship, and agency will be enlarged not diminished. As the concept of superself displaces that of individual selfhood, the brotherhood of man and its operating principle—equal dignity for all—become self-evident and self-enforcing. Nothing in this perspective bars belief in a Deity for those so inclined. Having said that, it’s implicit in this way of beholding selfhood that if there were a God, He’d want us to behave as if there weren’t. Like any good parent, He’d want to see us wean ourselves and grow up.
The superself, with its inherent co-creation and co-agency, not only transforms our relationships with each other, it also provides a new perspective on death. As mentioned, it’s arguable whether selves survive the death of the bodies in which they’re encoded. But, survivability is much less problematic for superselves. Why? Because they are dispersed and so, like the Internet that was designed to survive nuclear war, provide a more redundant and robust defense against extinction. As William Blake noted three centuries ago:
The generations of men run on in the tide of Time,
But leave their destin’d lineaments permanent for ever and ever.
In the same sense that the soul is deemed to survive the death of the individual, the wenome survives the disintegration of the body and the mind. The absence of a particular individual, as defined by a unique genome and menome, puts hardly a dent in the wenome. The building blocks of superselfhood can be thought of as genes, memes, and wemes. All three encodings are subject to evolutionary pressure.
Although some may feel this reformulation of selfhood asks them to give up the store, it will gradually become apparent that it’s only the storefront that requires a do-over. To give up standalone selfhood in exchange for a open-ended leadership role in cosmic evolution is a trade-off that many will find attractive.
As Norbert Wiener, the Father of Cybernetics, wrote in 1949:
We can be humble and live a good life with the
aid of machines, or we can be arrogant and die.
Robert W. Fuller is an author and independent scholar from Berkeley, CA. His most recent book is The Rowan Tree: A Novel.