A thought experiment about evolution
(An improved and updated version of this material has appeared in my book Why Materialism Is Baloney. The version below is kept for legacy purposes.)
|Do we see the world through distortive glasses? Image source: Wikipedia.|
I want to invite you today for a thought experiment. Let us suppose that the key tenets of our scientific, material-reductionist paradigm are all correct. According to this worldview, reality is objective and independent of mind; mind and its conscious perceptions are a by-product of the matter of the brain; and the brain, along with our ability to understand nature, has evolved through natural selection favoring survival of the fittest. Still according to this worldview, life has evolved within a space-time fabric where the interplay of matter and energy gives rise to the set of objective phenomena we call reality. Let us imagine this reality as a collection of objects in the canvas of space-time.
As the first living organisms evolved, they were immersed in the same space-time canvas populated by all the other objects that make up reality: rocks, water, sand, air, other living beings, etc. They also had perceptual mechanisms that gave them indirect access to these other objects: for instance, eyes that allowed them to form internal, subjective images of the objects populating the reality they were immersed in. The game of life consisted in optimizing one’s behavior in the dynamics of all those objects so to increase one’s chances of surviving and reproducing. Now note that, still according to the current scientific paradigm, because a living being only has access to its own internal images – not to the objects populating reality – its choices for implementing its survival strategy are entirely based on those images alone.
The images are constructed according to the architecture of the living being’s nervous system, which is itself, as postulated, a result of evolution through natural selection. An obvious question is thus: What would the optimal mapping between objects and subjective images be so to optimize survival? A mapping between two spaces – the objective space of objects and the mental, subjective space of images – can, mathematically speaking, assume infinite forms. One of these possible forms is the identity mapping: to each object in the space 'out there' corresponds a unique, analogous image in the subjective space 'in here.' Such one-to-one mapping, again, is just one possibility and should not, in principle, be assumed to be the most effective one as far as survival is concerned.
Indeed, many of the objects in the space 'out there' (that is, objective reality) may be irrelevant to survival to the extent that they cannot influence the physical body whose survival is being optimized for. For instance, my own work in the field of artificial neural networks has shown that nervous systems can evolve to advantageously discard the representation of objects whose corresponding images would just increase the amount of 'noise' in the nervous system. Other objects may indeed be relevant to survival in different ways, but mostly according to their relative differences, so that a mapping that altered and distorted their true attributes (like location, behavior, appearance, autonomy, intensity, etc.) so to highlight these relative differences could conceivably favor survival. Again, in another one of my earlier scientific works, it has been very clearly shown that certain artificial nervous systems perform much better when failing to fully or accurately represent the data available to them. Beyond my own work, a wealth of data on pre-processing systems for artificial neural networks shows that one-to-one mappings between objects and subjective images are often not optimal. Artificial nervous systems using these advantageous pre-processing schemes would, thus, ‘see’ a world very, very different from what is actually 'out there.' Their perception of reality would hardly resemble reality, but instead be set up, through evolution, to 'transform' reality and optimize their own chances of survival. In essence, they would live in a hallucinated theater.
You see, evolution would, most certainly, favor mappings between objects (that is, reality) and subjective images (that is, perceptions) that favored survival, whether such mappings would accurately or completely represent reality or not. After all, the variable being optimized for here is not representation accuracy or completeness, but survival.
And now here we are: highly evolved organisms with the unique ability to create scientific models of reality. And yet, we naively make an assumption that our own models seem to render highly suspicious: we assume that what we see, or otherwise perceive, can be accurately mapped one-to-one onto the ‘real reality out there.’ We assume that the subjective images in our minds correspond perfectly to the objects of reality. We assume, thus, that we have complete and undistorted access to that reality. This is a contradiction: there is no reason to believe that our brains would have evolved to represent reality completely and as-is; they would, instead, have evolved to represent it in whatever incomplete or distorted way favored survival the most. Therefore, as evolved creatures, we simply have no way to tell what is really going on. And although our technological instruments do broaden our perception mechanisms beyond what nature has provided us with, they are ultimately also limited to what we can perceive as far as our ability to build them, and perceive their outputs.
So we end up with a profound contradiction: if we are to be consistent with the scientific paradigm, we cannot trust that what we see is what is actually going on; we may, for all we know, be living in an elaborate, brain-constructed hallucination of reality that happens to maximize our chances of survival. However, the very scientific paradigm that tells us this was itself built upon the very assumption that what we perceive corresponds accurately to nature. If that assumption cannot be made, then can we trust the conclusions of our scientific paradigm to begin with?