Within this generation, scientists could come up with machines that are smarter than humans – and although the human brain is still ahead in the race, technology is catching up fast.
This weekend, scientists from the Simgularity Institute for Aritficial Intelligence debated the concept of smarter-than-human intelligence and how to achieve this goal.
The point at which technology overtakes human intelligence is known as the Singularity, with artificial intelligence being the best-understood example, and brain-computer interfaces already on the drawing board.
A central tenet of the science of Singularity is that our model of a world containing smarter-than-human intelligence is impossible to model.
Human intelligence is the foundation of human technology, the institute explains, and if technology can turn around and enhance intelligence, this closes the loop, creating a positive feedback effect – smarter minds will be more effective at building still smarter minds.
While speed alone isn't the only indicator of intelligence, there is compelling evidence that technology could soon overtake the human brain in terms of processing and neuron speed.
Human neurons operate by sending electrochemical signals that propagate at a top speed of 150 meters per second along the fastest neurons. By comparison, the speed of light is 300-million meters per second – 2-million times greater.
Similarly, most human neurons can spike a maximum of 200 times per second; even this may overstate the information-processing capability of neurons, since most modern theories of neural information-processing call for information to be carried by the frequency of the spike train rather than individual signals.
By comparison, speeds in modern computer chips are currently at around 2GHz – a 10-millionfold difference – and still increasing exponentially.
Humans also face an upper limit on the size of their brains. The current estimate is that the typical human brain contains something like a hundred billion neurons and a hundred trillion synapses. That's an enormous amount of sheer brute computational force by comparison with today's computers.
However, in the computing industry, benchmarks increase exponentially, typically with a doubling time of one to two years – we all know about Moore's Law.
By contrast, the entire five-million-year evolution of modern humans from primates involved a threefold increase in brain capacity and a sixfold increase in prefrontal cortex. We cannot increase our brainpower beyond this; in fact, we gradually lose neurons as we age.
The real heart of the Singularity, however, is the idea of better intelligence or smarter minds – humans are not just bigger chimps; we are better chimps.
What smarter-than-human really means, says the Institute, is almost impossible to define because we aren't there yet and cannot know what it will look like.