Douglas Hofstadter - I Am a Strange Loop

It’s not my aim here to attack Searle in detail (that would take a whole dreary chapter), but to point out how widespread is the tacit assumption that the level of the most primordial physical components of a brain must also be the level at which the brain’s most complex and elusive mental properties reside. Just as many aspects of a mineral (its density, its color, its magnetism or lack thereof, its optical reflectivity, its thermal and electrical conductivity, its elasticity, its heat capacity, how fast sound spreads through it, and on and on) are properties that come from how its billions of atomic constituents interact and form high-level patterns, so mental properties of the brain reside not on the level of a single tiny constituent but on the level of vast abstract patterns involving those constituents.

Dealing with brains as multi-level systems is essential if we are to make even the slightest progress in analyzing elusive mental phenomena such as perception, concepts, thinking, consciousness, “I”, free will, and so forth. Trying to localize a concept or a sensation or a memory (etc.) down to a single neuron makes no sense at all. Even localization to a higher level of structure, such as a column in the cerebral cortex (these are small structures containing on the order of forty neurons, and they exhibit a more complex collective behavior than single neurons do), makes no sense when it comes to aspects of thinking like analogy-making or the spontaneous bubbling-up of episodes from long ago.

Levels and Forces in the Brain

I once saw a book whose title was “Molecular Gods: How Molecules Determine Our Behavior”. Although I didn’t buy it, its title stimulated many thoughts in my brain. (What is a thought in a brain ? Is a thought really inside a brain? Is a thought made of molecules?) Indeed, the very fact that I soon placed the book back up on the shelf is a perfect example of the kinds of thoughts that its title triggered in my brain. What exactly determined my behavior that day ( e.g., my interest in the book, my pondering about its title, my decision not to buy it)? Was it some molecules inside my brain that made me reshelve it? Or was it some ideas in my brain? What is the proper way to talk about what was going on in my head as I first flipped through that book and then put it back?

At the time, I was reading books by many different writers on the brain, and in one of them I came across a chapter by the neurologist Roger Sperry, which not only was written with a special zest but also expressed a point of view that resonated strongly with my own intuitions. I would like to quote here a short passage from Sperry’s essay “Mind, Brain, and Humanist Values”, which I find particularly provocative.

In my own hypothetical brain model, conscious awareness does get representation as a very real causal agent and rates an important place in the causal sequence and chain of control in brain events, in which it appears as an active, operational force….

To put it very simply, it comes down to the issue of who pushes whom around in the population of causal forces that occupy the cranium. It is a matter, in other words, of straightening out the peck-order hierarchy among intracranial control agents. There exists within the cranium a whole world of diverse causal forces; what is more, there are forces within forces within forces, as in no other cubic half-foot of universe that we know….

To make a long story short, if one keeps climbing upward in the chain of command within the brain, one finds at the very top those over-all organizational forces and dynamic properties of the large patterns of cerebral excitation that are correlated with mental states or psychic activity…. Near the apex of this command system in the brain…. we find ideas.

Man over the chimpanzee has ideas and ideals. In the brain model proposed here, the causal potency of an idea, or an ideal, becomes just as real as that of a molecule, a cell, or a nerve impulse. Ideas cause ideas and help evolve new ideas. They interact with each other and with other mental forces in the same brain, in neighboring brains, and, thanks to global communication, in far distant, foreign brains. And they also interact with the external surroundings to produce in toto a burstwise advance in evolution that is far beyond anything to hit the evolutionary scene yet, including the emergence of the living cell.

Who Shoves Whom Around Inside the Cranium?

Yes, reader, I ask you: Who shoves whom around in the tangled megaganglion that is your brain, and who shoves whom around in “this teetering bulb of dread and dream” that is mine? (The marvelously evocative phrase in quotes, serving also as this chapter’s title, is taken from “The Floor” by American poet Russell Edson.)

Sperry’s pecking-order query puts its finger on what we need to know about ourselves — or, more pointedly, about our selves. What was really going on in that fine brain on that fine day when, allegedly, something calling itself “I” did something called “deciding”, after which a jointed appendage moved in a fluid fashion and a book found itself back where it had been just a few seconds before? Was there truly something referable-to as “I” that was “shoving around” various physical brain structures, resulting in the sending of certain carefully coordinated messages through nerve fibers and the consequent moving of shoulder, elbow, wrist, and fingers in a certain complex pattern that left the book upright in its original spot — or, contrariwise, were there merely myriads of microscopic physical processes (quantum-mechanical collisions involving electrons, photons, gluons, quarks, and so forth) taking place in that localized region of the spatiotemporal continuum that poet Edson dubbed a “teetering bulb”?

Do dreads and dreams, hopes and griefs, ideas and beliefs, interests and doubts, infatuations and envies, memories and ambitions, bouts of nostalgia and floods of empathy, flashes of guilt and sparks of genius, play any role in the world of physical objects? Do such pure abstractions have causal powers? Can they shove massive things around, or are they just impotent fictions? Can a blurry, intangible “I” dictate to concrete physical objects such as electrons or muscles (or for that matter, books) what to do?

Have religious beliefs caused any wars, or have all wars just been caused by the interactions of quintillions (to underestimate the truth absurdly) of infinitesimal particles according to the laws of physics? Does fire cause smoke? Do cars cause smog? Do drones cause boredom? Do jokes cause laughter? Do smiles cause swoons? Does love cause marriage? Or, in the end, are there just myriads of particles pushing each other around according to the laws of physics — leaving, in the end, no room for selves or souls, dreads or dreams, love or marriage, smiles or swoons, jokes or laughter, drones or boredom, cars or smog, or even smoke or fire?

Thermodynamics and Statistical Mechanics

I grew up with a physicist for a father, and to me it was natural to see physics as underlying every last thing that happened in the universe. Even as a very young boy, I knew from popular science books that chemical reactions were a consequence of the physics of interacting atoms, and when I became more sophisticated, I saw molecular biology as the result of the laws of physics acting on complex molecules. In short, I grew up seeing no room for “extra” forces in the world, over and above the four basic forces that physicists had identified (gravity, electromagnetism, and two types of nuclear force — strong and weak).

But how, as I grew older, did I reconcile that rock-solid belief with my additional convictions that evolution caused hearts to evolve, that religious dogmas have caused wars, that nostalgia inspired Chopin to write a certain étude, that intense professional jealousy has caused the writing of many a nasty book review, and so forth and so on? These easily graspable macroscopic causal forces seem radically different from the four ineffable forces of physics that I was sure caused every event in the universe.