PRINCETON, New Jersey — Thirty years ago, Australian vessels, with the government's blessing, killed sperm whales off the West Australian coast. Last month, Australia led international protests against Japan's plan to kill 50 humpback whales. Japan, under mounting pressure, announced that it would suspend the plan for a year or two. The change in public opinion about whaling has been dramatic, and not only in Australia.

Greenpeace began the protests against Australian whaling, and the government appointed ex-judge Sydney Frost to head an inquiry into the practice. As a concerned Australian and a philosophy professor working on the ethics of our treatment of animals, I made a submission.

I did not argue that whaling should stop because whales are endangered. I knew that many expert ecologists and marine biologists would make that claim. Instead, I argued that whales are social mammals with big brains, capable of enjoying life and of feeling pain — and not only physical pain, but very likely also distress at the loss of one of their group.