by John B. Carnett: Photo by John B. Carnett

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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: â€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!â€

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.

The word â€robot†originated almost a century ago. Czech dramatist Karel Capek first used the term in his 1921 play R.U.R. (for â€Rossum´s Universal Robotsâ€), creating it from the Czech word â€robota,†meaning obligatory work. In the play, he describes the invention of intelligent biomechanical machines intended as servants for their human creators. While lacking charm and goodwill, his robots brought together all the elements of machine intelligence: vision, touch sensitivity, pattern recognition, decision making, world knowledge, fine motor coordination and even a measure of common sense.

Capek intended his intelligent machines to be evil in their perfection, their perfect rationality scornful of human frailty. These robots ultimately rise up against their masters and destroy all humankind, a dystopian notion that has been echoed in much science fiction since.

The specter of machine intelligence enslaving its creators has continued to impress itself on the public consciousness. But more significantly, Capek´s robots introduced the idea of the robot as an imitation or substitute for a human being. The idea has been reinforced throughout the 20th century, as androids engaged the popular imagination in fiction and film, from Rosie to C-3PO and the Terminator.

The first generation of modern robots were, however, a far cry from these anthropomorphic visions, and most robot builders have made no attempt to mimic humans. The Unimate, a popular assembly-line robot from the 1960s, was capable only of moving its one arm in several directions and opening and closing its gripper. Today there are more than two million Roomba robots scurrying around performing a task (vacuuming) that used to be done by humans, but they look more like fast turtles than maids. Most robots will continue to be utilitarian devices designed to carry out specific tasks. But when we think of the word â€robot,†Capek´s century-old concept of machines made in our own image still dominates our imagination and inspires our goals.