O Repugnance, Where Is Thy Sting?

In philosophical discussions of ethics one often hears the complaint that arguments rely too heavily on intuitions. Of course intuitions also play a similar in other areas of philosophy: A system of modal logic may be rejected on the ground that it implies a counterintuitive view of counterfactuals; theories of justification may be rejected on ground that they have counterintuitive implications for knowledge, and theories of meaning may be rejected when they are judged to have intuitively unacceptable implications for a theory of reference. But intuitions are not a reliable guide to truth, and there is a point to the objection that they should not be used in the wrong way. As Derek Parfit has shown, many of our intuitions about the value of well being turn out to be confusing and contradictory when we apply them to populations of varying size and constituency. There is no normative theory of population choice that does not have seriously counterintuitive implications.