In the summer season of 2009, the Israeli neuroscientist Henry Markram strode onto the TED phase in Oxford, England, and made an immodest proposition: Within a decade, he said, he and his colleagues would construct a complete simulation of the human brain inside a supercomputer. They ‘d currently spent years mapping the cells in the neocortex, the supposed seat of thought and perception. “It’s a bit like going and cataloging a piece of the tropical rain forest,” Markram explained. “The number of trees does it have? What shapes are the trees?” Now his team would develop a virtual tropical rain forest in silicon, from which they hoped expert system would organically emerge. If all worked out, he quipped, possibly the simulated brain would offer a follow-up TED talk, beamed in by hologram.
Markram’s idea– that we might comprehend the nature of biological intelligence by simulating its forms— was rooted in a long custom, going back to the work of the Spanish anatomist and Nobel laureate Santiago Ramón y Cajal. In the late 19 th century, C