Could our lack of theoretical insight in some of the most basic questions in biology in general, and consciousness in particular, be related to us having missed a third aspect of reality, which upon discovery will be seen to always have been there, equally ordinary as space and time, but so far somehow overlooked in scientific descriptions?
Is the arena of physics, constructed out of space and time with matter/energy tightly interwoven with space and time, sufficient to fully describe all of our material world? The most fundamental debates in cognitive science take a firm "yes" for granted. The question of the nature of mind then leaves open only two options: either a form of reductionism, or a form of escapism. The latter option, a dualist belief in a separate immaterial mental realm has fallen out of favor, largely because of the astounding successes of natural science. The former, reductionism, is all that is left, whether it is presented in a crude form (denial of consciousness as real or important) or in a more fancy form (using terms like emergence, as if that would have any additional explanatory power).
The question I ask myself is whether there could not be another equally fundamental aspect to reality, on a par with space and time, and just as much part of the material world?
Imagine that some tribe had no clear concept of time. Thinking only in terms of space, they would have a neat way to locate everything in space, and they would scoff at superstitious notions that somehow there would be "something else", wholly other than space and the material objects contained therein. Of course they would see things change, but both during and after each change everything has its location, and the change would be interpreted as a series of purely spatial configurations.
Yet such a geometric view of the world is not very practical. In physics and in daily life we use time in an equally fundamental way as space. Even though everything is already "filled up" with space, similarly everything participates in time. Trying to explain that to the people of the no-time tribe may be difficult. They will see the attempt at introducing time as trying to sneak in a second type of space, perhaps a spooky, ethereal space, more refined in some way, imbued with different powers and possibilities, but still as a geometric something, since it is in these terms that they are trained to think. And they probably would see no need for such a parallel pseudo-space.
In contrast, we do not consider time to be in any way less "physical" than space. Neither time nor space can be measured as such, but only through what they make possible: distances, durations, motion. While space and time are in some sense abstractions, and not perceivable as such, they are enormously helpful concepts in ordering everything that is perceivable into a coherent picture. Perhaps our problems in coming up with a coherent picture of mental phenomena tells us that we need another abstraction, another condition of possibility for phenomena in this world, this very material world we have always lived in.
Could it be that we are like that tribe of geometers, and that we have so far overlooked a third aspect of reality, even though it may be staring us in the face? Greek mathematicians used time to make their mathematical drawings and construct their theories, yet they disregarded time as non essential in favor of a Platonic view of unchanging eternal truths. It took two thousand years until Newton and Leibniz invented infinitesimal calculus, which opened the door for time to finally enter mathematics, thus making mathematical physics possible.
To reframe my question: could our lack of theoretical insight in some of the most basic questions in biology in general, and consciousness in particular, be related to us having missed a third aspect of reality, which upon discovery will be seen to always have been there, equally ordinary as space and time, but so far somehow overlooked in scientific descriptions?
Although I don't know the answer, I suspect we will stumble upon it through a trigger that will come from engineering. Newton did not work in a vacuum. He built upon what Galileo, Descartes, Huygens and others had discovered before him, and many of those earlier investigations were triggered by concrete applications, in particular the construction of powerful canons calling for better ways to compute ballistic orbits. Another example is the invention of thermodynamics. It took almost two centuries for Newtonian mechanics to come to grips with time irreversibility. Of course, every physicist had seen how stirring sugar in a cup of tea is not reversible, but until thermodynamics and statistical mechanics came along, that aspect of reality had mostly been ignored. The engineering problems posed by the invention of steam engines were what forced a deeper thinking about time reversibility.
Perhaps current engineering challenges, from quantum computers to robotics to attempts to simulate large-scale neural interactions, will trigger a fresh way of looking at the arena of space and time, perchance finding that we have been overlooking an aspect of material reality that has been quietly with us all along.
Piet Hut, professor of astrophysics at the Institute for Advanced Study, in Princeton, is involved in the project of building GRAPEs, the world's fastest special-purpose computers.