Now, at the beginning of a new century, Toulmin sums up a lifetime of work and issues a call to redress the balance between rationality and reasonableness. His vision does not reject the valuable fruits of science and technology, but requires awareness of the human consequences of our discoveries. Toulmin argues for the need to confront the challenge of an uncertain and unpredictable world, not with inflexible ideologies and abstract theories, but by returning to a more humane and compassionate form of reason, one that accepts the variability and complexity that is human nature as an essential beginning for all intellectual inquiry.