Toulmin: Thirty-five years. At that time, if you had said to Rachel Carson in her last years that by the mid 1990s no government in the world with any pretension to respectability would fail to have some kind of environmental protection agency, it would have appeared quite incredible to her.

This is a major change in the agenda of politics, and it's a change which moves precisely in the direction that represents a return from, shall we say, Descartes to Erasmus. I remain charmed by Erasmus's famous essay, In Praise of Folly, which is a prophylactic against the quest for certainty.