This means that at some point computing power will skyrocket and when it does computers will be able to do everything, Kurzweil believes, that our brains can do. People will be able to scan their brains' contents, including their ability to produce states of consciousness, onto a computer and leave the physical body behind. It will be the end of humanity as we know it.
Kurzweil thinks that, at present rates of increase in the power of our computers, this point, what he calls The Singularity, will be reached by 2045.
Lev Grossman at Time has a fascinating essay on Kurzweil and his ideas. Here are a few excerpts:
Computers are getting faster. Everybody knows that. Also, computers are getting faster faster — that is, the rate at which they're getting faster is increasing.Grossman also discusses some of the objections to Kurzweil's vision, but one which he doesn't mention and which would seem to be a strong possibility is that when growth of anything - population, global temperature, speed - goes "hockey stick" (i.e. the graph looks like a hockey stick laying on its spine with the blade pointed up), some constraining factor always gets activated which causes the growth to stop or collapse. I don't know what the constraints might be on exponentially increasing computing power, or at what point they would kick in, but I wouldn't be surprised if it doesn't turn out that there are such limits on how powerful a computer can get.
So if computers are getting so much faster, so incredibly fast, there might conceivably come a moment when they are capable of something comparable to human intelligence. Artificial intelligence. All that horsepower could be put in the service of emulating whatever it is our brains are doing when they create consciousness — not just doing arithmetic very quickly or composing piano music but also driving cars, writing books, making ethical decisions, appreciating fancy paintings, making witty observations at cocktail parties.
The one thing all these theories have in common is the transformation of our species into something that is no longer recognizable as such to humanity circa 2011. This transformation has a name: the Singularity.
We will successfully reverse-engineer the human brain by the mid-2020s. By the end of that decade, computers will be capable of human-level intelligence. Kurzweil puts the date of the Singularity — never say he's not conservative — at 2045. In that year, he estimates, given the vast increases in computing power and the vast reductions in the cost of same, the quantity of artificial intelligence created will be about a billion times the sum of all the human intelligence that exists today.
Once hyper-intelligent artificial intelligences arise, armed with advanced nanotechnology, they'll really be able to wrestle with the vastly complex, systemic problems associated with aging in humans. Alternatively, by then we'll be able to transfer our minds to sturdier vessels such as computers and robots. He and many other Singularitarians take seriously the proposition that many people who are alive today will wind up being functionally immortal.
Anyway, what is just as interesting about Grossman's article is his discussion of how telomerase is being used to slow or reverse the aging process. You'll have to read the article to see what that's all about.