It is essential, particularly for making judgments about social welfare, to compare different individuals’ gains and losses and to take note of their relative affluence, which cannot be immediately deduced only from people’s rankings of social alternatives. It is also important to examine which types of clusters of preference rankings are problematic for different types of voting procedures.
比较不同个体的利益和损失、注意他们的相对丰裕程度（这无法通过人们对社会方案的排序立刻推得）是至关重要的，特别是在做出关于社会福利的判断方面。同样重要的是考察哪些类型的偏好排列窜（cluster）对于不同类型的投票程序有问题。