Ray Kurzweil is teaching computers how to read better—one more step in the march of technological progress. The 66-year-old inventor and futurist thinks that by 2030, computers won't only be able to understand ordinary spoken language but will show emotions too. Next to arrive will be the "singularity"—a term he popularized nearly a decade ago for the point at which humans and computers will merge as one. That will happen in 2045, he predicts, when human intelligence will be enhanced a billion-fold thanks to high-tech brain extensions.

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