Human experience is marked by a refusal to obey our limitations. We've escaped the ground, we've escaped the planet, and now, after thousands of years of effort, our quest to build machines that emulate our own appearance, movement and intelligence is leading us to the point where we will escape the two most fundamental confines of all: our bodies and our minds. Once this point comes-once the accelerating pace of technological change allows us to build machines that not only equal but surpass human intelligence-we'll see cyborgs (machine-enhanced humans like the Six Million Dollar Man), androids (human-robot hybrids like Data in Star Trek) and other combinations beyond what we can even imagine.
Although the ancient Greeks were among the first to build machines that could emulate the intelligence and natural movements of people (developments invigorated by the Greeks' musings that human intelligence might also be governed by natural laws), these efforts flowered in the European Renaissance, which produced the first androids with lifelike movements. These included a mandolin-playing lady, constructed in 1540 by Italian inventor Gianello Torriano. In 1772 Swiss watchmaker Pierre Jacquet-Droz built a pensive child named L'crivain (The Writer) that could write passages with a pen. L'crivain's brain was a mechanical computer that was impressive for its complexity even by today's standards.
Such inventions led scientists and philosophers to speculate that the human brain itself was just an elaborate automaton. Wilhelm Leibniz, a contemporary of Isaac Newton, wrote around 1700: "What if these theories are really true, and we were magically shrunk and put into someone's brain while he was thinking. We would see all the pumps, pistons, gears and levers working away, and we would be able to describe their workings completely, in mechanical terms, thereby completely describing the thought processes of the brain. But that description would nowhere contain any mention of thought! It would contain nothing but descriptions of pumps, pistons, levers!"
Leibniz was on to something. There are indeed pumps, pistons and levers inside our brain-we now recognize them as neurotransmitters, ion channels and the other molecular components of the neural machinery. And although we don't yet fully understand the details of how these little machines create thought, our ignorance won't last much longer.