Learned ignorance

June 6, 2001

Graduation season has arrived, and commencement speakers everywhere are praising the virtues of education. I have often been a commencement speaker, but lately I have begun to wonder if knowledge should come with a warning label on it: “Caution: contents are volatile and may cause burns.”

The most obvious kind of dangerous knowledge is scientific knowledge. Now that we know how to split atoms, splice genes, clone life and swap parts, what shall we do with that knowledge? While most scientists recognize a clear boundary between pure and applied science, there are few border guards on duty. Should scientists police themselves? Should government step in? How much control should big business have over the research that it funds? Fearing censorship on one side and exploitation on the other, the scientific establishment has been slow to answer such questions. Meanwhile, we have ample evidence that dangerous knowledge can be hard to control.

Theoretical physicist J. Robert Oppenheimer, who played a major role in the creation of the atomic bomb, had a change of heart when he saw what his invention could do. Two years after Hiroshima and Nagasaki, he made a remarkable confession. “In some sort of crude sense which no vulgarity, no humor, no overstatement can quite extinguish, the physicists have known sin, and this is a knowledge which they cannot lose.”

This quote comes from a book called Forbidden Knowledge, in which literary scholar Roger Shattuck explores “the dark side of human ingenuity and imagination.” Beginning with Greek myth and ending with the Marquis de Sade, Shattuck revives the ancient notion of taboo. He claims that “taboo” refers to an object, place, person or action in which “holiness and pollution are not yet differentiated.” The taboo works in two directions at once. It not only protects the potential trespasser from harm; it also protects the forbidden entity from violation.

Anyone who has read the Bible should recognize the territory. Whether God is warning Adam and Eve to steer clear of one particular tree or aiming a wrecking ball at the Tower of Babel, the message is consistent. There is a divinely set limit to human knowledge, which mortals trespass at their own risk. Like all taboos, this one cuts both ways. Yes, God would like a little privacy. More important, God cares for human life, which can stand only so much divine radiation without blowing entirely apart. “You cannot see my face,” God warned Moses on Mount Sinai, “for no one shall see me and live.”

This brings us to a second kind of dangerous knowledge, which is knowledge of God. Most of the great souls who have devoted themselves to researching it seem to have come pretty quickly to the same conclusion. “God approaches our minds by receding from them,” Thomas Merton once wrote. “We know Him better after our minds have let Him go.” Even those who believe that Jesus provides them with a backstage pass eventually come to the Mount of Transfiguration, where awe seals their eyes and shuts their mouths.

A little over 500 years ago, a German cleric named Nicholas of Cusa was sailing home from Constantinople when something happened to him aboard ship that changed his life and thought forever. He called it a “celestial gift,” a direct experience of the God who had always slipped right past his intellect. As beyond language as this gift was, Nicholas wrote around it in his most famous work, which he called “On Learned Ignorance.” It is not an easy read. Using mathematical formulae and geometric figures that overheat the mind, Nicholas often wraps up an illustration by saying something such as, “It is very clearly established from what has been said that the absolutely maximum is both incomprehensibly understandable and ineffably nameable; we shall offer an even clearer explanation of this later on.”

But he keeps circling back on the one thing he knows to be true: that God is the unknown infinite who dwells in light inaccessible from before time and forever. Human beings trying to approach that God are like night owls trying to look at the sun. The fact that we go on being blinded does not keep us from wanting to look, but Nicholas will not call this desire our sin. Instead, he calls it the God-given desire “to know that we do not know.” “If we can attain this completely,” he says, “we will attain learned ignorance. For nothing more perfect comes to a person, even the most zealous in learning, than to be found most learned in the ignorance that is uniquely one’s own.”

In Nicholas’s scheme, the dumbest people in the world are those who think they know. Their certainty about what is true not only pits them against each other; it also prevents them from learning anything new. This is truly dangerous knowledge. They do not know that they do not know, and their unlearned ignorance keeps them in the dark about most things that matter.

According to Nobel Prize–winning physicist Richard Feynman, uncertainty is as high a value in science as it is in religion. “If you know that you are not sure, you have a chance to improve the situation,” he said. That is why he defended “the great value of a satisfactory philosophy of ignorance,” which is willing to leave the door to the unknown ajar.

Such learned ignorance is no safeguard against dangerous knowledge, as both H-bombs and holy wars attest, but it does provide a different goal for those who seek the highest education possible. To know that we do not know is the beginning of wisdom.