PITTSBURGH—Announcing a crucial breakthrough in the effort to create machines that accurately simulate human behavior, researchers at Carnegie Mellon University said Monday they had built the first robot with the capacity to suppress its emotions. "This is the holy grail of artificial intelligence," said project director Kate Tillman, explaining that the robot instantly performs millions of computations to ensure feelings of unresolved anger and simmering resentment remain deeply buried within its complex circuitry. "We felt we were on the right track when we brought up a personal shortcoming and it paced around the lab muttering, but when it started breaking eye contact and changing the subject, we knew we had accomplished something revolutionary." Tillman added that with its superior processing power, the robot could apply for clerical work and settle for the nearest available partner 10,000 times faster than a human being.