In Part 6. of this series (which starts here), I discussed the fantastic power of “error”—how the compounding of tiny infidelities over long periods can yield a grand diversity of properties in self-replicating molecules/molecular systems. And yet, alongside the physical complexities that arise through this Natural Selection, there lies another kind of complexity—a complexity so mysterious to us we’ve made-up all sorts of gods, spirits, demons and alternate realities to explain how it came to be. I am speaking of the inner-experience of ourselves. Not just our consciousness, but our conscience, our intuitions, logic, desires, emotions, pains, and pleasures. I am talking about what all started with our ability to sense.
Sensing the outside world is a really big deal—even if it is something so mild as “seeing” brightness or “tasting” the presence of a certain chemical—it starts us on a path of internal complexity, a complexity that neuroscience shows corresponds to externally observable structures. These structures are usually, but not always, located in the brain, and should they be injured they can alter or even destroy the internal sense to which they correspond. We call this “brain damage.”
The evolution of internal-sensing, like the evolution of external structures, builds on it’s own back—that is to say, the ability to sense heat combined with the ability to sense an increase in one’s heart-rate both contribute to a “higher-order” sense of fear.
The evolution of our senses has followed a sequence that goes (very roughly) something like this:
Now one should not be tempted to think of this progression as a hierarchy; I am not proposing that the pinnacle of natural selection is a Starbuck-drinking, Whole-Food shopping, relatively moral, male homo-sapiens as pictured above. It’s important to keep in mind that in a sense every living thing is just as “evolved” as every other—we all lie at the (current) end of that great path of errors I previously spoke on. Certain types of errors have simply accumulated in certain types of organisms, giving them particular characteristics (and advantages)—while other characteristics have accumulated in others. The internal-sensing capabilities of our species are, in a way, no more highly-evolved than a star-nosed mole’s specialized capabilities to score a meal in places we’d not long survive.
In any case, it is in this sequence of our developing inner-experience that many people will say I have gone too far. They will not accept that the brain and body are responsible for the rich vastness of our interior lives or that combinations of brain functions present a solution to the “problem of consciousness.”
But that discussion we will save for next time…