In its search for the grand unifying principles of nature, mainstream science often looks down. Considering an object to be no more than the sum of its parts, a complex thing is reduced to a conglomerate of basic atomic primitives and nothing more.
Taken to the extreme, we end up with the reductive physicalist view that the only real things in the universe are mindless physical atoms, and everything else simply emerges from their mechanical interactions.
Richard Dawkins presents a flavor of this radically reductive view on life in his bestselling book — The Selfish Gene. A living organism is reduced to a collection of cells, whose structure and configuration are said to be determined by the self-replicating genetic sequences encoded in its physical DNA.
Rejecting the possibility of any fundamental organization at a higher level, this view attempts to reductively explain all organic behavior and structure as emerging from the mechanistic work of selfish genetic replicators.
The only kind of entity that has to exist in order for life to arise, anywhere in the universe, is the immortal replicator.
Reductive physicalism paints a picture of life as arising from the genetically programmed assembly of molecular primitives through an unguided physical process. But is that all there really is?
Michael Levin’s lab studies cellular development and regeneration in various species. Through their research, they found that the specific arrangement of organs and tissues in an organism isn’t dictated exclusively by its genes. Instead, an organism’s morphological development is largely controlled by an integrated network of bioelectric fields.
They extensively studied the planarian — a humble flatworm with extraordinary regenerative abilities. You’ve probably heard of the lizard that can regrow its tail. But when a planarian is cut in two, each half grows into a whole new planarian.
Researchers found that by cutting a piece of the planarian and inducing changes to the bioelectric potential across its membranes during the regeneration process, they were able to grow a two-headed planarian.
Now, something even more interesting happens when we cut off a piece of this two-headed planarian. Even without any external intervention, this piece grows into another two-headed planarian. It’s almost as if the bioelectric stimulus imprinted a memory onto the collective of cells. And no genes were edited here!
In another experiment, researchers mutated the faces of tadpoles to create malformed “Picasso tadpoles”. If each cell simply followed a predetermined genetic blueprint during development, one would expect the frogs they evolved into to be deformed as well.
But surprisingly, in most cases, they went on to produce rather normal-looking frogs. Somehow, the cells were able to actively respond to the perturbation and coordinate their individual actions to achieve the desired configuration.
It would appear that the organism as an integrated whole possesses a high-level understanding of the target morphology that isn’t reducible to the product of simple rule-following by its component parts.
It’s also striking how much the behavior of cells during development mirrors the workings of our own minds. Exhibiting characteristics like memory, an understanding of goal states, and adaptation to changes in the environment. This leads you to wonder if these cells can actually think.
A potent mix of reductive and anthropocentric views leads to the popular myth that there’s something unique about the structure of our brains that grants us the ability to think. But it would appear that these capabilities may be more widespread than our fragile egos would like to admit.
Research in the field of basal cognition shows that even the behavior of so-called “lower organisms” like bacteria can be understood through a cognitive framework.
Escherichia coli is a common bacteria that lives in our gut. In our intestinal tract, the sugar lactose precedes maltose. Researchers found that the bacteria have learned to exploit this by activating their maltose pathways when they detect the presence of lactose.
The crucial question is whether this behavior is adaptive or a mere physical fact of the chemical process. And by conditioning a culture of this bacteria to grow in an environment with just lactose and no maltose, they found that it loses its maltose-anticipatory reaction to lactose. How Pavlovian!
Certain bacteria, like Myxococcus xanthus, can perceive inert foreign objects like glass beads — which cannot be explained by a simple sensitivity to chemical gradients — and exhibit tactic behavior towards those objects. They also demonstrate the ability to move, self-organize into multicellular swarms, and even prey on other species of bacteria. It appears that life down below is no less interesting than life up above.
Experiments have also shown cognitive characteristics apparent in the behavior of diverse living organisms such as plants and fungi. It seems that life everywhere, when observed closely appears to think.
Taking it a step further, if we accept that all these organisms possess some capacity to think, it’s not hard to imagine that they also have a kind of subjective conscious experience — that there is something it is like to be them. This raises a couple of interesting points to explore.
First, the idea that mental idioms can be applied to the behavior of various lifeforms. Rather than shackling ourselves to describing all phenomena in contrived material formalisms, we are free to use notions that we are more intimately familiar with — like wanting, planning, learning.
Another point to consider is that subjective consciousness may be scale-invariant. And all beings, regardless of their place in our constructed hierarchies, are treated the same.
The physicalist paradigm often treats consciousness as a property that mysteriously emerges from material interactions above a particular size or level of complexity. And the discontinuity in the process of physical evolution that suddenly makes a system conscious always seemed a little arbitrary and capricious to me.
An implicit assumption of the physicalist worldview is that consciousness is a one-way product of physical structure. But what if it played a fundamental role in creating the structure in the first place?
As the studies in morphology have shown, characteristics of consciousness appear to manifest even during the process of development. This challenges the notion of a simplistic unidirectional relationship between physical matter and consciousness.
These points strike at the very heart of the notion of a physical basis for consciousness. Now, some may still try to rescue physicalism by arguing that we only need to adjust the scale of our investigation and look for a more subtle physical mechanism underlying consciousness in living beings.
But there may be something fundamentally irreconcilable about applying the principles of physical reduction to explain subjective conscious experience. The philosopher Thomas Nagel explores this point in his famous essay, “What Is It Like to Be a Bat?”
We appear to be faced with a general difficulty about psychophysical reduction. In other areas the process of reduction is a move in the direction of greater objectivity, toward a more accurate view of the real nature of things. […]
Experience itself, however, does not seem to fit the pattern. […] If the subjective character of experience is fully comprehensible only from one point of view, then any shift to greater objectivity — that is, less attachment to a specific viewpoint — does not take us nearer to the real nature of the phenomenon: it takes us farther away from it.
Subjective consciousness underlies how we experience things in every moment, while the notion of an objective physical realm is just another abstraction in our experience.
Not to say that each of these perspectives doesn’t have its own place. But if I had to pick one that I believed lay at the foundation of all lifeforms, I would choose the one that is forever immediately apparent.