  Another distinction that can often account for other examples of apparent diversity is also worth mentioning. As David Braybrooke suggests, there is a difference between ‘adventitious needs’ and ‘course-of-life’ needs (Braybrooke 1987, 29). Adventitious needs are those that become important given a certain project, practice, or activity. But within one society not all citizens may wish to undertake those activities. The needs may not be shared by all, even if it is true that the item claimed to be needed is indeed essential to undertake that activity. By contrast, a course-of-life need is one that is widely shared and is not dependent on particular projects; during the course of human lives lived in that society, one typically needs items on the list.