Peter Singer on Derek Parfit’s On What Matters:
Last month, however, saw a major philosophical event: the publication of Derek Parfit’s long-awaited book On What Matters. Until now, Parfit, who is Emeritus Fellow of All Souls College, Oxford, had written only one book, Reasons and Persons, which appeared in 1984, to great acclaim. Parfit’s entirely secular arguments, and the comprehensive way in which he tackles alternative positions, have, for the first time in decades, put those who reject objectivism in ethics on the defensive.
On What Matters is a book of daunting length: two large volumes, totaling more than 1,400 pages, of densely argued text. But the core of the argument comes in the first 400 pages, which is not an insurmountable challenge for the intellectually curious – particularly given that Parfit, in the best tradition of English-language philosophy, always strives for lucidity, never using obscure words where simple ones will do. Each sentence is straightforward, the argument is clear, and Parfit often uses vivid examples to make his points. Thus, the book is an intellectual treat for anyone who wants to understand not so much “what matters” as whether anything really can matter, in an objective sense.
Many people assume that rationality is always instrumental: reason can tell us only how to get what we want, but our basic wants and desires are beyond the scope of reasoning. Not so, Parfit argues. Just as we can grasp the truth that 1 + 1 = 2, so we can see that I have a reason to avoid suffering agony at some future time, regardless of whether I now care about, or have desires about, whether I will suffer agony at that time. We can also have reasons (though not always conclusive reasons) to prevent others from suffering agony. Such self-evident normative truths provide the basis for Parfit’s defense of objectivity in ethics.