Thinking About Thinking
Here's the opening of a work in progress....
Seventy-four thousand years ago, humanity nearly went extinct. A super-volcano at what's now Sumatra's Lake Toba erupted with a strength more than a thousand times greater than that of Mount St. Helens in 1981. Over 800 cubic kilometers of ash filled the skies of the northern hemisphere, lowering global temperatures and pushing a climate already on the verge of an ice age over the edge. Genetic evidence shows that at this time – many anthropologists say as a result – the population of Homo sapiens dropped to as low as a few thousand families.
It seems to have been a recurring pattern: Severe changes to the global environment put enormous stresses on our ancestors. From about 2.3 million years ago, up until about 10,000 years ago, the Earth went through a convulsion of glacial events, some (like the post-Toba period) coming on in as little as a few decades.
How did we survive? By getting smarter. Neurophysiologist William Calvin argues persuasively that modern human cognition – including sophisticated language and the capacity to plan ahead – evolved due to the demands of this succession of rapid environmental changes. Neither as strong, nor as swift, nor as stealthy as our competitors, the hominid advantage was versatility. We know that the complexity of our tools increased dramatically over the course of this period. But in such harsh conditions, tools weren't enough – survival required cooperation, and that meant improved communication and planning. According to Calvin, over this relentless series of whiplash climate changes, simple language developed syntax and formal structure, and a rough capacity to target a moving animal with a thrown rock evolved into brain structures sensitized to looking ahead at possible risks around the corner.
Our present century may not be quite as perilous as an ice age in the aftermath of a super-volcano, but it is abundantly clear that the next few decades will pose enormous challenges to human civilization. It's not simply climate disruption, although that's certainly a massive threat. The end of the fossil fuel era, global food web fragility, population density and pandemic disease, as well as the emergence of radically transformative bio- and nanotechnologies – all of these offer ample opportunity for broad social and economic disruption, even devastation. And as good as the human brain has become at planning ahead, we're still biased by evolution to look for near-term, simple threats. Subtle, long-term risks, particularly those involving complex, global processes, remain devilishly hard to manage.
But here's an optimistic scenario for you: if the next several decades are as bad as some of us fear they could be, we can respond, and survive, the way our species has done time and again: By getting smarter. Only this time, we don't have to rely solely on natural evolutionary processes to boost intelligence. We can do it ourselves. Indeed, the process is already underway.