Today is July 4th, a day when Americans reflect on the value of freedom and the costs and sacrifices required for it. So it is an appropriate day to reflect on America’s deepest political aspirations.

Nah. Let’s talk about our brains. The neocortex is where all our fancy thinking takes place. The neocortex wraps around the core of our brain, and if you could carefully unwrap it and lay it flat it would be about the size of a dinner napkin, and about 3 millimeters thick. The neocortex consists of 150,000 cortical columns, which we might think of as separate processing units involving hundreds of thousands of neurons. According to research at Jeff Hawkins’ company Numenta (and as explained in his fascinating recent book, A Thousand Brains), these cortical columns are capable of modeling patches of our experience (he calls them “reference frames”) and setting our expectations of what we should experience next, at any given moment. [Note: the remarks that follow are inspired by Hawkins’ book, but shouldn’t be taken as a faithful representation of it.]
The neocortex’s complexity is considerable, but not infinite, and what’s most surprising is that such a relatively small network—you can fold it up and put it in your head—is capable of understanding calculus and making up jaunty little tunes and comparing Kierkegaard to Heidegger, not to mention doing all three in a single afternoon.