From Plato to Descartes to Berkely to the majority of religious believers today, the idea that mind (or spirit, soul, or consciousness) is a fundamentally different “substance” from matter and can exist independently of matter has been accepted as a matter of course. Another way of putting this is that we tend to believe that our mind, which stands above our brain, can cause our brain to make decisions and direct our body to do this or that. Furthermore, my mind can survive the obliteration of my brain, and I can continue to be “me” in a post-mortem existence.
Before I jumped into the crystal-blue waters of Cozumel during our 20th anniversary cruise in April, I had been reading and highlighting a good number of passages in an ebook on my smartphone. These highlights, of course, were not synchronized back to the “cloud” while on the ship before I jumped into said crystal-blue waters with my phone left inadvertently in the pocket of my swim shorts. I’ve retroactively gleaned a few highlights to share with you from this fascinating book entitled Consciousness: Confessions of a Romantic Reductionist by neuroscientist Christof Koch (2012, MIT Press).
People willingly concede that when it comes to nuclear physics or kidney dialysis, specialized knowledge is essential. But let the conversation turn to consciousness, and everybody chimes in, on the assumption that they are all entitled to their own pet theory in the absence of pertinent facts. Nothing could be further from the truth. An immense stockpile of psychological, neurobiological, and medical knowledge about the brain and the mind has accumulated. The travails of more than fifty thousand brain and cognitive scientists worldwide add thousands of new studies each year to this vast collection (Koch 2012, 41).
It’s not hard to miss between the lines of the relatively well-mannered paragraph above a sense of frustration on the part of author after hearing countless know-it-alls trash the consensus views of neuroscientists who are the most familiar with how the brain and consciousness function. Most of us non-pilots would never presume to lecture an experienced airline pilot on how to avoid a stall, but we think ourselves qualified to say things to neuroscientists like, “Well, your study of the brain is admirable as far as it goes, but it’s never going to explain how mere matter gives rise to consciousness and our sense of agency. You can’t determine what makes me me just by looking at circuits and connections and currents in my brain.”
This was a challenging read for me. Sure, there were some technical discussions that were over my head, but that wasn’t my greatest difficulty. Instead, it was some of the “wu”-like concepts that made me wonder how someone as brilliant as Dr. Koch can believe things that border on the mystical and the implausible. For instance, he gives provisional assent to the notion that consciousness is largely a function of two factors: differentiation and integration, the latter denoted by the Greek letter phi:
Integrated information theory introduces a precise measure capturing the extent of consciousness called Φ, or phi (and pronounced “fi”). Expressed in bits, Φ quantifies the reduction of uncertainty that occurs in a system, above and beyond the information generated independently by its parts, when that system enters a particular state (Koch 2012, 127)
A little bit mysterious, perhaps, but nothing eyebrow-raising until he goes on to discuss the pan-psychic implications of this theory. According to Koch, any network that informationally connects any element to any other element in the universe experiences a certain degree of consciousness, from the brain of a fly, to computer networks (especially the World Wide Web), and even to every atom in the universe (Koch 2012, 131). Consciousness is not an either-or phenomenon but is a continuum from near zero to the palpable self-awareness of humans. I suppose my misgivings about this theory are rooted in common sense, but common sense isn’t always the best guide to ferreting out the nature of reality. Otherwise, there would be no need for scientific experimentation to correct our mistaken intuition that a canon ball falls faster than a feather in a vacuum, for example. I’m willing to grant that humans and dogs and mice are conscious to some extent, but it’s a little harder to imagine what goes on the brain of a fly or of a worm, let alone what consciousness could possibly mean with reference to the Internet or to a rock or to the universe as a whole.
Despite this bit of borderline wu, I found Koch’s research to be intriguing as a whole. We live in an exciting time, a time in which we’re finally beginning to develop the tools to study empirically the questions that have dogged philosophers with no end in sight for millennia. For instance, Koch and his team are able to use a technique called optogenetics to study the effects of temporarily turning on and off groups of similar neurons in specific regions of the brain in rats. They accomplish this by introducing harmless viruses into the neurons of the brain, and when they shine a light with a specific wavelength on these neurons, they turn these neurons on or off. Using this technique, it’s possible to determine which neurons are required for consciousness. If you turn off certain neurons, the rats remain conscious, but if you turn off certain other neurons, the rats succumb to a zombilike state. In other words, it’s possible to identify fairly precisely which groups of neurons are required to maintain a conscious state.
Koch argues that consciousness is nothing more than an emergent property of the integrated network of neurons in our brain, and no invocation of a spiritual realm or extra-natural laws or substances is required to explain it. Just as the gases hydrogen and oxygen combine to form water whose properties are completely different from its constituent parts, so physical neuronal activity in the brain leads to consciousness whose properties seem to point to a realm outside the physical world. Our reluctance to accept that consciousness is “merely” an emergent property of physical brains mirrors an earlier reluctance to accept that the instructions for life itself could be encoded in a physical package. Since the discovery of DNA by Crick and Watson in the 1950s, however, we now know that all the instructions for forming life are encapsulated in physical DNA.
England’s leading geneticist William Bateson in 1916 could not imagine how life could possibly be encoded with physical instructions:
The supposition that particles of chromatin, indistinguishable from each other and indeed almost homogeneous under any known test, can by their material nature confer all the properties of life surpasses the range of even the most convinced materialism (Koch 2012, 117).
Koch goes on to describe the consensus views on the nature of life before and after Crick and Watson’s discovery of DNA:
To explain life, scholars invoked a mysterious vitalistic force, Aristotle’s entelechy, Schopenhauer’s phenomenal will, or Bergson’s élan vital. Others, the physicist Erwin Schrödinger of the eponymous equation among them, postulated new laws of physics. Chemists could not imagine that the exact sequence of four types of nucleotides in a string-like molecule held the key. Geneticists underestimated the ability of macromolecules to store prodigious amounts of information. They failed to comprehend the amazing specificity of proteins shaped by the action of natural selection over several billion years. But this particular puzzle was eventually solved. We now know that life is an emergent phenomenon and can, ultimately, be reduced to chemistry and physics. No vitalistic force or energy separates the inorganic, dead world from the organic world of the living (Koch 2012, 117).
Granted, when it comes to the study of mind and consciousness, we have not reached the equivalent of our DNA moment to prove that consciousness is no more than a physical phenomenon, but Bateson’s confidence that life cannot be explained in physical terms should stand as a cautionary tale for those who still insist that mind and consciousness require an otherworldly component. If physicalism or materialism is true, then in theory it should be possible to build a working, conscious brain out of physical parts. This is the aim of the Blue Brain Project, which has succeeded in reverse engineering and simulating parts of a rat brain at the molecular level and which aims to do the same for entire human brain by the year 2023. That seems a little optimistic to me, given the uncertain economy and the capricious nature of public funding for such projects, but it’s not inconceivable that within my lifetime (I just turned 44), someone somewhere will have developed an artificial brain that speaks and thinks like we do.
If and when this occurs, it will be an unmitigated triumph for physicalism and a repudiation of all the philosophers who have separated mind and matter as two fundamentally incommensurable substances. Yet I predict that those who currently insist on the necessity of a spiritual realm to explain consciousness will continue to believe in a spiritual realm, somehow readjusting the goalposts, just as the goalposts were adjusted in the wake of the discovery that physical DNA is sufficient to encode life.
Somewhat surprising to me was Koch’s confession in his final chapter that, though he grew up Catholic and left religion behind as he embraced scientific reductionism, he is not an atheist but believes in a deistic creator, one who brought into existence matter and the laws of nature, leaving the universe to unfold and evolve into what it is today. He considers that a creator must have been responsible for the exquisitely fine-tuned constants of nature that allow for a life-supporting universe to exist. In addition, he appeals to our intuition that “nothing” is a more natural state than “something,” so without a creator, we should expect there to be nothing rather than something. He concedes that there can be no final proof for the existence of God but finds it more plausible to believe in God than in a gratuitous multiverse to explain the problem of fine tuning. I won’t rehash here the arguments atheists have typically marshaled to answer his reasons for believing in God. I have the greatest respect for a scientist like Koch who can use optogenetics to probe the foundations of consciousness, even if I find his arguments for the existence of God to be less than conclusive.
My reading of Koch’s arguments for the existence of God came on the heels of a protracted discussion on the timing of Jesus’ return on my blog, in which very intelligent individuals went head to head, certain of what they believed yet unable to convince the other to budge in the slightest. The conjunction of these two unrelated experiences gave me pause. We all know what it’s like to feel certain of what we believe. I believe without a shadow of a doubt that the earth revolves around the sun, yet for over 150 years after Copernicus advanced his heliocentric theory, there was a protracted, heated debate between the heliocentrists and the geocentrists, both of whom were certain of their respective positions. Yet the psychological phenomenon of certainty was not a sure guide to truth for at least one of the two parties in the debate. This raises questions for me regarding the nature of my own certainty on a number of topics. I do not want to fall into the morass of postmodern relativism, where anything can be “true for you” or “true for me,” because I can’t help but think there’s a real world out there and that some ideas of ours reflect the way the world really is more than other ideas. My best guess is that no god exists, but I could be wrong. My best guess is that the universe is not conscious in any way, but I could be wrong. My best guess is that consciousness is entirely physical, but I could be wrong. I just wish more of us could admit the tentative nature of what we often believe with great certainty, particularly when our beliefs lack empirical support. That said, I do look forward to the day when some age-old questions can be put to rest empirically, questions like whether mind is made merely of matter of or something more. We may well be living in the exciting generation that will provide a definitive answer.