June 2010

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…

NEXT: Part 8. More on Body and Soul


In Part 5. of this series (which starts here), I introduced the notion of a molecule that copies. And if you remember, the copying did not occur with complete fidelity—that is, the copy was not an exact duplicate of the original.

Now, I’m going to refer to this infidelity as a “mistake” or “error”, but I’d like to point out that strictly speaking it’s not a mistake or error at all—because there’s no intention behind the copying. Simply, the molecule that copies doesn’t make exact copies, that’s just the way it is—it’s not “trying” to do it “right”, and therefore it cannot make mistakes or introduce errors. I’m using those words because it’s easier to type “error” than “a copy without perfect fidelity.”

So by way of review, let’s put together what we have so far in the Model of Everything:

In the past 5 posts we’ve managed to get from sub-atomic particles to the emergence of simple life forms, but clearly we’ve got to account for the vast gap between the kind of life in the diagram above to the complex beings that we are. And yet the gap is bridged by a rather simple process: natural selection.

Just as oceans build beaches by the accumulation of tiny grains of sand—given enough time, tiny copying mistakes can yield an amazing diversity of life. How can the accumulation of errors result in such an assortment? Because natural selection saves what works.

As soon as an error provides an advantage, it is saved. How? By the organism’s survival. The surviving organism’s offspring, then—armed with that beneficial change—not only carry the change forward, but also create changes to the change. Why? Because in the business of making copies, mistakes never stop.

Of course other factors add to the final result of all this change, copies that find themselves in water will survive if their random mistakes allow the organism to better live in water, and those on land will survive with an accumulation of land-mistakes. In the end, the variety is wonderful:

Yes, we are the spat-out guts of dead stars combined and recombined through billions of years of accumulated successful mistakes. T-Rexes, narwhals, cute little kittens, George Bush—we all share this amazing pedigree.

NEXT: Part 7. The Inner Life of Living Things

In Part 4. of this series (which starts here), I discussed two key ideas: 1. How to get from small stuff (like atoms) to big stuff (like stars and planets), and 2. How this process ultimately yields atoms that are themselves larger and more complex. Here is a table of those atoms (elements):

Elements of course allow chemical properties to emerge. How that emergence fits in with my Model of Everything (thus far) is shown below:

So, to continue building the model, then, it’s necessary to introduce a fantastically-important and not-as-yet-understood process within chemistry–a process that has occurred at least once in our past: abiogenesis.

Abiogenesis is a scary-looking word that simply means getting from the stuff of non-life to the stuff of life–a big step to be sure–and one that represents another level of emergence in my model. In short, it seems that the chemistry responsible for molecules like H2O and amino acids also can yield a molecule that copies. And THAT is a special molecule indeed.

This self-copying, self-replicating molecule is what life needs to get going, and whatever the original variant of this molecule looked like, it was almost certainly different than the replicators central to life today–molecules like RNA and DNA. The originator of replication would have been a simpler version of these and may have gotten its start piggy-backing on shapes constructed by inorganic compounds–such as the crystal lattice of minerals. Repeating crystalline structures are not living things (in any sense we think of), but if naturally-occurring organic molecules hitched a ride on just the right template, one with a particular connectivity, an arrangement that allowed the already-repeating pattern to be picked up by an organic molecule–well that’s just the sort of thing a planet replete with organic compounds can work into something special.

Here’s a molecule making copies now:

And look, it made a “mistake” on copy B–there’s a circle shape where the original had a line:

I can hardly overstate the importance of such infidelity, such faithlessness to the original. This trait is crucial to yielding complexity and “improvement”. Without infidelity we would not be here today (perhaps for some of us in more ways than one). Without infidelity there can be no variation, and without variation, no single copy of “A” will ever be better at making copies than any other.

As a quick aside, I find it interesting that most world religions see our straying from the “straight” and “faithful” path as “sin”, but our natural inability to be “true” is the formula of our success. Imperfection is the engine of creativity; it is the “soul” of life. But let us not push our metaphors too far (at least not yet). The point of this post is really just to get to something like these:

Now maybe they aren’t the most complex examples of life, but our interest is not in complexity–it’s in existence. This property of chemistry is almost too-wonderful, intriguing, amazing–the idea that atoms, if brought together in just the right way, will yield a molecule that copies.

NEXT: Part 6. The Power of Error