First posted 21 Oct 2003. These days, I find myself thinking that consciousness 'came first' rather than evolving from smaller bits. The 'arrow of time' and 2nd Law strike me as reflections of an irreducible asymmetry between moments.
Nature abhors differences. Or, dropping the anthropomorphism, over time, entropy increases. Randomness, disorder is always in the ascendancy within any closed, equilibrium system. The universe is such a system. So how do we explain ourselves?
We are impressive examples of order on a number of levels. We are alive. That takes a fair bit of organisation - in our case several trillion cells of 200 different types arrange themselves according to a recipe inherited via one cell each from mother and father. These cells exchange information with one another and create proteins to do their work. They regulate their own environments and internal conditions.
Amazingly, they act in such a mutually supportive way that they form a larger life - one with sense organs to interact with the external world, with the ability to find its own food, extract energy from it, deliver that energy throughout its body and eliminate the waste products of its cells' chemical reactions.
In an even more flagrant seeming violation of nature's overarching randomisation, one particular organ, our brain, is able to create order from the chaos of input it receives from its body and its environment. A solitary example: light rays strike the retina, electro-chemical impulses shoot to visual centres, and behold, we form a working visual model of the space around us.
Are we in breach of the 2nd law of thermodynamics? No. We are neither closed systems nor equilibrium ones. We take in energy. We dissipate heat as we work. Our local, seeming violations of the 2nd law are minuscule within the context of the universe's continuing expansion and cooling. It's just as well that the increasing order inherent in our evolution and existence is not a foul, because it is continuing.
Particles joined into atoms. Light atoms fused into heavier ones. Atoms joined to form molecules. Molecules stumbled upon an auto-catalytic formula that could keep itself going and replicate itself into further generations. This formula incorporated other chemicals, in other groupings, and cooperated to create cells. Cells of different types, co-operating with one another, out-produced ones that did not, so multi-celled organisms sprang forth. These organisms mutated, feathered out into niches.
Complex life forms evolved alongside the ever-efficient bacteria who worked to perfect life's simplest strategy. Life forms that co-operated with one another out-produced ones who did not. Symbiotic relationships flourished. Families and packs operated together. Language arrived. Tribes formed. Societies blossomed. Economies converged. Technology flourished. Who among us thinks we have reached the end?
I think that the 2nd law makes most sense in probabilistic terms. There are infinitely many more disordered combinations than there are ordered ones, so as time unfolds from a relatively well-ordered point, it is much more likely (effectively certain) that the overall degree of order will decrease rather than increase. Think of gas molecules in a room. Have we ever seen them all gathered in one corner? Or arranged in the shape of a smiley face? Yet we are that smiley face. Highly unlikely in the grand scheme of things.
We are here. That, I think, is best explained in terms of conditional probability, which looks at the likelihood something will happen, given that a certain other thing has happened. Given that the ratios between atomic weights and electron energy levels are as they are, given that the universe didn’t implode under its own weight but rather expanded, given that our Sun has had a relatively long and stable life, given that the Earth is a certain distance from the Sun, given that mix of chemicals on the earth contains an abundance of certain elements, we are not that unlikely at all. Given that 'we' (in the form of existence, then life, then consciousness) made it to any point in our history, the next step was actually bound to happen, if given enough time. Explained thus, incrementally and conditionally, we are not so unexpected.
But in the larger picture and the longest time-frames, the odds remain insurmountably against us. Microbe attack, perhaps launched by one of our own? Nuclear holocaust? Asteroid strike? It needn't end so spectacularly. We now know (or think that we do) that the universe is not just expanding but doing so at an accelerating rate. This means that, ultimately, the battle will be lost. Entropy will win. Even if we (that is, our very distant descendants) were to escape our Sun's white dwarf and red giant stages by fleeing our solar system, eventually the energy we would need to retrieve resources for life would be greater than the energy conferred by the resources once we reached them. Game over.
But despair not. This local bubble of order, speaking just for himself, says it is still worth the trip. Our little outpost almost certainly has further to go. What else might we, as Being's greatest (known) lab experiment, see, learn, reveal, become? As far as we know, Earth's animal life is the universe's only eye on itself, we humans its only contemplators of itself. A pretty important role. Let's enjoy it while it lasts, even if we are burdened with knowing that it must end.