A Philosophy beyond the Limits of Rationality ; in Pursuit of Theoretical Certainty, We've Lost What's Reasonable

Article excerpt

According to Stephen Toulmin, a professor at the University of Southern California, there are signs all around us, from medicine to economics, that modern science needs an infusion of common sense.

As 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. As the goal of reason, likelihood was replaced by certainty; nature, including human nature, was replaced by Newton's nature, predictable and self-consistent.

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. And so research universities may resemble madhouses, each researcher locked in his dream of reason, incapable of addressing the needs of others or of society at large.

For instance, when a doctor delivers the results of the diagnosis - "There's nothing we can do" - he all too often washes his hands of the patient. Indeed, young doctors "still tend to see the first patient they 'lose' as a total failure; it takes more mature physicians to see that the manner of a patient's dying is not less a mark of success or failure than the fact of his or her death."

This book is a call for "reflective practitioners," people more willing to be "reasonable" than strictly "rational." Toulmin bases his concept of reasonableness on the model of "knack," the instinctive knowledge that cooks and musicians and baseball players exhibit as they go about their jobs. While modern reason is expressed by strings of logic and statistical columns, knack is rooted in non-verbal knowledge.

The ancients understood knack. …