The turmoil and brutality of the twentieth century have made it increasingly difficult to maintain faith in the ability of reason to fashion a stable and peaceful world. After the ravages of global conflict and a Cold War that divided the world's loyalties, how are we to master our doubts and face the twenty-first century with hope? In Return to Reason , Stephen Toulmin argues that the potential for reason to improve our lives has been hampered by a serious imbalance in our pursuit of knowledge. The centuries-old dominance of rationality, a mathematical mode of reasoning modeled on theory and universal certainties, has diminished the value of reasonableness, a system of humane judgments based on personal experience and practice. To this day, academic disciplines such as economics and professions such as law and medicine often value expert knowledge and abstract models above the testimony of diverse cultures and the practical experience of individuals. Now, at the beginning of a new century, Toulmin sums up a lifetime of distinguished work and issues a powerful 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 diversity and complexity that is human nature as an essential beginning for all intellectual inquiry. Henry Luce Professor at the University of Southern California after a career at Oxford, Cambridge, and Northwestern, the 79-year-old Toulmin champions "reasonableness" against the imperialistic strictures of formal reasoning. He pursues two distinctions between formal and informal arguments and between the hard sciences and other claims to knowledge. "Horses need plants, and plants need sunlight, so horses need sunlight" is a formal argument depending on logical rules, meanings, and facts. If the facts are right, the conclusion is certain. The suggestion that it is more likely that Caesar first invaded Britain to stop cross-channel raiding than that he was pursuing a runaway mistress is an informal argument depending on historical and cultural contexts. All such arguments are inconclusive, but Toulmin argues that "pragmatism and skepticism are the beginning of a wisdom that is better than the dreams of the rationalists." Toulmin further states that Newtonian physics is a bad model for social science for instance, in trying to be universal, economics has sometimes caused local disasters and he believes that, by getting people together to grasp one another's stories, we can achieve reasonableness. But can we? Everyone could tell the bad guys in Westerns, and Trekkies knew Captain Kirk acted for the best, but not everyone thinks Hollywood got everything right. In a world in which moviemakers, publishers, politicians, and religious leaders influence the stories we get to think about, a little demonstrable proof would be handy. Leslie Armour, Univ. of Ottawa, Ont. Copyright 2001 Reed Business Information, Inc. In elegant prose, Toulmin...contends that advocates of pure reason have forgotten "the complementary concept of reasonableness," a model of intellectual practice focused on values and experience rather than facts and theories. His rich conceptual history outlines the ways in which early modern science and philosophy separated reasonableness from rationality, and the resulting imbalance in all academic disciplines. ( Publishers Weekly ) Toulmin shows in this readable and fascinating account, the practice of reason that produced modern science goes back to the 17th century, when traditional reasonableness was replaced by the model of geometry...Eventually--and this is perhaps one of Toulmin's most challenging insights--what came of this change is the system of disciplines that govern modern intellectual life...Throughout Return to Reason , Toulmin calmly addresses complex situations arising in modern disciplines. Indeed, the knack he shows for reasonableness illustrates his thesis. His book is both a diagnosis and, by example, a cure for what ails our scientific culture. (Thomas D'Evelyn Christian Science Monitor 2001-08-16) There is now a 'loss of confidence'...in our traditional ideas about rationality, according to Toulmin. Especially among those in the humanities, he argues, the claims of rationality have been progressively challenged over the last 20 or 30 years, to the point of being sidelined. This is a common complaint and not exactly news, but Toulmin does not merely bemoan and rant, as many others have done. He offers a diagnosis and a solution. Rationality has come under threat, he believes, because of the undue influence of classical mechanics and abstract mathematical methods on our idea