The Truth About Facts

Among the sillier aspects of the current electoral season is the way that each side tortures the other for supposed lies and distortions, often on the basis of partisan talking points or factoids drawn from a favorite ideological commentator or website. What is true, in the sense of being verifiable and well-founded, seems less important than what is helpful to the campaign.

A useful tonic at so depressing a moment is the mathematician Samuel Arbesman’s lively new book, “The Half-Life of Facts: Why Everything We Know Has an Expiration Date.” Arbesman’s subject is science, not politics; but candidates and their ardent supporters could learn much from his fascinating account of how both knowledge and errors spread.

Arbesman opens the book with an anecdote I first heard from one of my undergraduate physics professors: Until the 1950s, the scientific world was convinced that the human cell contained 48 chromosomes. Then researchers made a careful recount and discovered that the actual number was (as we now know) 46.

Or consider the following example: In February 1994, the journal Diabetes Care published an article carefully describing a mathematical model for determining glucose tolerance and other metabolic issues in diabetes patients. What neither the editors nor the author seemed to realize was that the newly discovered model was actually something very old: differential calculus.

Factual Citations

The paper derived, and announced as new, what Newton and Leibniz had discovered 300 years earlier. Yet it has received hundreds of citations in other scholarly publications and is still cited today.

Arbesman urges us not to be too hard on the author of the diabetes article. “Despite our technological advancement,” he writes, “knowledge can spread far slower than we might realize.” Even well-read scientists may end up replicating what has already been invented or discovered.

Arbesman isn’t offering some vulgar argument about skepticism; he’s hardly anti-science. His point, rather, is that not even the smartest people can know everything that is important; and even when they think they do, much of their “knowledge” is probably obsolete.

The dilemma is familiar to us from everyday life: one day red meat is good for us, the next day it’s bad, the next day it’s neutral. It isn’t unusual for nonexperts to throw up our hands, wishing we could get a clear answer. Arbesman doesn’t, as he could, blame the news media for rushing studies into the headlines without pausing to ask independent experts whether the studies are any good. Blame the nature of knowledge, he says: Scientific understandings change constantly, and the rapid spread of information is haphazard and full of mistakes.

That nobody can keep up with everything can lead to serious information failure. Arbesman points to a 1992 Harvard University examination of the literature on streptokinase, a protein that is still one of the leading treatments after a heart attack. The major study showing the effectiveness of the drug was published in 1988. The Harvard research discovered that had each of the many streptokinase studies (all the way back to 1959) taken into account the results of all the other studies of the drug, its effectiveness would have been conclusively demonstrated 15 years earlier.

The speed of change is part of the problem: “In addition to all of the cognitive biases we are saddled with, it is difficult for us to keep abreast of all the information around us.” We were generalists when young, he says, but later learned to specialize. Thus, curiously, the longer we live and the more we learn, the more “old” knowledge sits unexamined.

Factual Immaturity

The result? With respect to much if not most of what we think we know, “we remain stuck at the factual level of our grade-school selves.”

This is where our political classes should pause to take note of Arbesman’s thesis. Given the speed at which information propagates, errors spread just as quickly as truths. The errors, in turn, often go undetected by the recipients, who think they know the facts but are wrong.

“Luckily,” he writes, “there is a simple remedy: Be critical before spreading information and examine it to see what is true. Too often not knowing where one’s facts came from and whether it is well-founded at all is the source of an error.”

This kind of humility, to be sure, is no more common in politics than in science. Arbesman simply urges us to double-check our truths before we go about spreading them. Indeed, he approves of a trend many of us have tut-tutted: the way people are relying on their own memories less and search engines more: “The more we look things up, the more likely we are not to be caught unaware when we encounter a startling idea.”

Part of what we should inform ourselves about is what other people are looking into. Arbesman cites studies suggesting that collaborators make more progress when they are in close physical proximity than when they work at a distance.

As recently as 100 years ago, information traveled so slowly that researchers on different continents were unaware that they were duplicating one another’s work. Denied opportunities to collaborate, they discovered a good deal less than they could have.

In the past, Arbesman reminds us, significant discoveries were made by generalists without formal scientific training, working in environments that were anything but hospitable -- a point he illustrates using the cleverly chosen example of the debate over whether a man in Shakespeare’s position could have written his plays.

But discovery is getting harder. Arbesman borrows a phrase used by the economist Tyler Cowen: We have picked the low-hanging fruit. Much future learning will come only at great expense, in both money and time. For a nation (and a world) in financial crisis, the challenge of continuing to press the boundaries of knowledge is considerable.

Factual Advancement

Yet the journey is worth taking. Here again is a lesson for our politics. Partisans have an embarrassing tendency to rest comfortably on the certainties that have brought their movements this far. Arbesman reminds us that science advances precisely because researchers constantly challenge old truths, discarding them when the evidence points elsewhere. Our politicians and their acolytes might usefully learn from the example.

“The Half-Life of Facts” is easily one of the best books of the year on science. It would be a lovely irony were it to prove one of the best books on politics, too.

(Stephen L. Carter is a Bloomberg View columnist and a professor of law at Yale University. He is the author of “The Violence of Peace: America’s Wars in the Age of Obama,” and his most recent novel is “The Impeachment of Abraham Lincoln.” The opinions expressed are his own.)

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