In his recent book, The Singularity Is Near: When Humans Transcend Biology (Viking Adult, 2005), Kurzweil, 57, predicts that ultimately, human intelligence and computer intelligence will fuse and become indistinguishable. He recently told Computerworld how and when that might come about.

Your idea to reverse-engineer the human brain seems pretty far out. Until recently, we haven't had the tools to scan the brain with sufficient resolution. But there are five or six new scanning technologies. For the first time, we can see the brain creating our thoughts.

The amount of data we are gathering about the brain is doubling every year. As we get the data from particular regions, we can rather rapidly create detailed mathematical models of them. It's a conservative expectation that we will have a very accurate detailed simulation of all the regions of the brain by the late 2020s.

Ten quadrillion [1016] calculations per second is sufficient to emulate all the regions of the brain. Japan just announced two supercomputers that will achieve that by 2010.

The question arises, Are we intelligent enough to understand our own intelligence? Maybe that's a feature of complex systems -- they can't be so complex as to understand themselves. But it turns out that's not the case.