 The other two principal views both treat welfare as a mental rather than a material issue. The wish-based mental view uses each person’s wishes (i.e. preferences in the informal sense of that word) as the criterion of welfare (Sen 1979). A person is considered to have more welfare, the more her wishes are satisfied. If this view is applied within a utilitarian framework, then it gives rise to preference utilitarianism. This view of welfare has difficulties in dealing with misinformed and self-defeating wishes. It can also have difficulties with certain types of other-regarding wishes, e.g. malevolent ones. The usual way to deal with this is to require that preferences are filtered (“laundered”) and/or refined before they are used to judge a person’s welfare. 