This article has given me an idea about the new worst case scenario for preference utiltiarianism: A lot of computing power and an algorythm that will make different minds pop in and out of existence. Each time the mind has a different combination of preferences out of some vast template space for possible minds. And each time, the mind is turned off (forever) after a very brief period of existence. How much computing power and time would it need to force a preference utiltiarian to torture every human being on earth if that were the only way to prevent the simulation?