According to the worm theory, persons are (maximal) aggregates of person-stages existing at different times. Personites, on the other hand, are non-maximal aggregates of stages that are very much like persons. Their existence appears to make instances of prudential self-sacrifice morally problematic: the personites that exist at the time of the sacrifice but not at the time of the reward seem not to receive future compensation for their sacrifice. Instances of punishment appear to give rise to a similar problem. We (...) argue that these impressions arise from a mistaken assumption about the primary bearers of properties such as suffering, receiving compensation (in the future) and having (previously) committed a crime. According to the worm theory, stages, rather than persons or personites, possess these properties. Persons and personites have these properties only derivatively. As we show, once this clarification and related ones are made, the apparent moral problems raised by the existence of personites dissolve. (shrink)