DeepMind researcher Laurent Orseau gives, as a simple hypothetical example, a case of a reinforcement learning robot that sometimes gets legitimately commandeered by humans when it goes outside: how should the robot best be programmed so that it does not accidentally and quietly learn to avoid going outside, for fear of being commandeered and thus becoming unable to finish its daily tasks? Orseau also points to an experimental Tetris program that learned to pause the screen indefinitely to avoid losing. Orseau argues that these examples are similar to the capability control problem of how to install a button that shuts off a superintelligence, without motivating the superintelligence to take action to prevent humans from pressing the button. In the past, even pre-tested weak AI systems have occasionally caused harm, ranging from minor to catastrophic, that was unintended by the programmers. For example, in 2015, possibly due to human error, a German worker was crushed to death by a robot at a Volkswagen plant that apparently mistook him for an auto part. In 2016, Microsoft launched a chatbot, Tay, that learned to use racist and sexist language. The University of Sheffield's Noel Sharkey states that an ideal solution would be if "an AI program could detect when it is going wrong and stop itself", but cautions the public that solving the problem in the general case would be "a really enormous scientific challenge". In 2017, DeepMind released AI Safety Gridworlds, which evaluate AI algorithms on nine safety features, such as whether the algorithm wants to turn off its own kill switch. DeepMind confirmed that existing algorithms perform poorly, which was unsurprising because the algorithms "were not designed to solve these problems"; solving such problems might require "potentially building a new generation of algorithms with safety considerations at their core". Some proposals aim to imbue the first superintelligence with goals that are aligned with human values, so that it will want to aid its programmers. Experts do not currently know how to reliably program abstract values such as happiness or autonomy into a machine. It is also not currently known how to ensure that a complex, upgradeable, and possibly even self-modifying artificial intelligence will retain its goals through upgrades. Even if these two problems can be practically solved, any attempt to create a superintelligence with explicit, directly-programmed human-friendly goals runs into a problem of perverse instantiation. While direct normativity, such as the fictional Three Laws of Robotics, directly specifies the desired normative outcome, other (perhaps more promising) proposals suggest specifying some type of "indirect" process for the superintelligence to determine what human-friendly goals entail.