Back in 2008, the technologist Ray Kurzweil estimated that the processing power of the human brain was in the region of 20 quadrillion calculations per second and that, as soon as we developed a supercomputer fast enough, simulating the brain would just be a problem of getting the software right. It was announced last month that the world’s fastest supercomputer, China’s Tianhe-2, can carry out almost 34 quadrillion calculations per second, meaning that, according to Kurzweil, we have the potential to simulate one and two-thirds of a human brain inside a single machine.
The idea that we could fit “one and two-thirds” of our brain function in a computer may seem a little flippant but it is not an unreasonable conclusion if you think of the brain as primarily a calculating engine. If this seems a little distant from your everyday experience, the idea that the mind is this “computation at work” is an assumption so embedded in modern neuroscience that it’s almost impossible to find anyone arguing for a non-computational science of the brain. […]