 Mill first applies this test to what each of us desires for her own sake. His answer is that what each of us desires for her own sake is happiness (IV 3). We needn’t interpret Mill as endorsing psychological egoism at this point. Rather, he is saying when each of us does focus on her own ends or sake, we find that each cares about her own happiness. Another way to put Mill’s point is that prudential concern focuses on the agent’s happiness.