A Test for Consciousness How will we know when we ’ ve built a sentient computer ? By making it solve a simple puzzle

How would we know if a machine had taken on this seemingly ineffable quality of conscious awareness? Our strategy relies on the knowledge that only a conscious machine can demonstrate a subjective understanding of whether a scene depicted in some ordinary photograph is “right” or “wrong.” This ability to assemble a set of facts into a picture of reality that makes eminent sense—or know, say, that an elephant should not be perched on top of the Eiffel Tower—defines an essential property of the conscious mind. A roomful of IBM supercomputers, in contrast, still cannot fathom what makes sense in a scene. Understanding the attributes of a sentient machine will allow humans not only to understand the workings of our own brains but to prepare for that day, envisaged in science fiction, when we must learn to live with another form of conscious being that we ourselves created. This understanding may even allow us to address one of the most profound questions that has beset philosophers throughout the ages: What is consciousness?