India, July 4 -- I have been travelling through Britain these past weeks, speaking at Cambridge, at Oxford, and in the British Parliament on freedom, self-knowledge, and the climate crisis. Last Friday evening, at the London School of Economics, I sat in a long public dialogue with Professor Jonathan Birch on the question of animal sentience: how does one know whether very small creatures feel anything at all? It is a serious question, and Britain has taken it seriously. Professor Birch's research informed recent animal welfare legislation passed by the British Parliament, and in matters of animal protection, Britain is counted among the leading nations of the world.

That same evening, I went to Richmond Park, the great royal park on the...