Common Knowledge

"Well, that's your opinion" can swallow up all discussion. Some wonder how any knowledge, much less certainty, can be extracted from the gaudy variety of beliefs on display even within a single culture, much less across cultures. Others wave aside as outdated all empirical, reasoned attempts to establish knowledge—as, for example, the American presidential aide quoted in this passage from the New York Times:

The aide [to President George W. Bush] said that guys like me were "in what we call the reality-based community," which he defined as people who "believe that solutions emerge from your judicious study of discernible reality." I nodded and murmured something about Enlightenment principles and empiricism. He cut me off. "That's not the way the world really works anymore," he continued. "We're an empire now, and when we act, we create our own reality."¹ [End Page 429]

Might makes right; empire makes real. But should we in the academy be surprised, much less shocked, when politicians impatiently sweep aside "Enlightenment principles and empiricism"? Have scholars and scientists themselves not repeatedly and insistently doubted the adequacy, even the bare possibility, of the "judicious study of discernible reality" as conventionally understood? If venerable guidelines (the "Enlightenment model") for how to establish knowledge and test belief—and above all, how to tell them apart—are cast in doubt by those who pursue knowledge as their profession, is it any wonder that power rushes in to fill the vacuum left by truth? Is it really the case that we have only two alternatives?—either to embrace an incomplete, inaccurate Enlightenment model of knowledge and belief, or else to dismiss the "reality-based community" in the name of actions that create their own reality?² It is time to find a way out of this impasse.

The Enlightenment model for understanding knowledge, belief, and their relationship to each other is under attack on several fronts. Some protest its narrowness: humanists and social scientists point out that the model cannot make sense of the tacit knowledge by which pilots fly planes, the traditional knowledge by which indigenous peoples identify medicinal plants, the distributed knowledge by which a crew can steer a mammoth ship that none of them understands alone, the poetic knowledge by which as much of the world as possible is "accounted for," the contextual knowledge that sorts out the relevant from the irrelevant in every use of language.³ Others doubt the empirical adequacy of the model even as a description of the natural sciences. Historians, philosophers, and sociologists of science have argued that trust and know-how are essential to modern science as a collective and empirical undertaking and have further traced how the very objects of inquiry and the standards of what counts as knowledge have changed over time.⁴ Scientists for their part cannot recognize their workaday practices in the precepts of epistemology, as their memoirs amply document.⁵ Scholars who cultivate other fields of learning—such as history, philosophy, and philology—find it still more difficult to square the ways in which evidence and [End Page 430] arguments are carefully assembled in their disciplines with the descriptions and prescriptions of the Enlightenment model.

Outside of the academy, critics contest not so much the accuracy of the model as its relevance. Theologians seek to expand the realm of belief, sometimes construed as religious faith, sometimes as time-hallowed opinion, to absorb knowledge entirely within its boundaries. It would be natural, and it is fair, to object that the reservations of scholars and scientists about whether the Enlightenment model is empirically satisfactory are in a different class from those of critics, including religious critics, who reject empiricism altogether. But so long as the Enlightenment model is the only intellectually respectable account of knowledge and belief, any and all arguments that weaken it may be used to strengthen the hand of those who disdain any kind of reasoned argument and empirical evidence.⁶ Such unintended complicity is no fantasy: witness the political exploitation of the uncertainty...