In The Philosophy of John Stuart Mill, Alan Ryan suggests there is an underlying unity of conception in Mill's philosophical writing. He identifies this single idea as ‘inductivism’ and, in the first of the two chapters devoted to Mill's ethics, he states that ‘once we understand how this concept of rationality holds together his views on mathematics and justice’, we will find that much ‘light can be shed on the dark places of Mill's philosophy’. No mention will be made in the present essay of Mill's opinions on mathematics, and it is only incidentally concerned with his ideas about justice. However, it shares Ryan's premise that an inductivist interpretation of Mill's moral philosophy is likely to be most enlightening. In particular, our aim is to show how this approach can brighten up two undeniably murky spots in Utilitarianism: the ‘proof passage’ of chapter 4, and the distinction between higher and lower pleasures in chapter 2.