I FIRST HEARD Peter Singer speak at the University of Western Australia (UWA) in the summer of 2009. The subject was the ethics of what we eat, and the tone of the talk was open and generous. Some in the audience were hardcore animal-rights people, as one would expect at a Singer gig. But the philosopher’s message was that ethical eating is, in fact, a pretty complex matter, bearing not only on animal welfare but also on economic justice and the environmental impact of agriculture, and that what counted as ethical behaviour in one sphere was often difficult to reconcile with ethical behaviour in others. His advice was therefore to do what we could, advice I for one resolved to follow before hogging into the free wine and nibbles around the Beaux-Arts-style reflecting pool. 

The second time I heard Singer speak was in the winter of 2015, and the atmosphere was chillier all-round. Again, the venue was UWA, and (again) the philosopher’s demeanour was congenial. But the message had a harder edge. The lecture was entitled ‘The most good you can do’ – based on Singer’s new book of that name, a follow-up to The Life You Can Save (2009). Beginning with a sketch of our scandalous levels of global inequality, Singer argued that morally serious people should dedicate a percentage of their income to charities and NGOs in the business of alleviating the poor world’s suffering.