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A Guide for These Uncertain Times

Stuck explaining how something you know is the best scientific case by someone who keeps throwing "uncertainty" in your face? Here's a little primer on answering those critics.
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The language of science doesn’t always lend itself to making persuasive arguments. There’s the theory of evolution. The overwhelming consensus on climate change. And the uncertainty, of, well, just about everything.

Recall how Michelle Nijhuis discussed the breed of "doubt makers" for us several years ago:

... Scientists are allergic to certainty; no matter how strong the evidence, an alternative explanation may exist somewhere, and scientists are trained to acknowledge that possibility. And scientists continue to argue about important aspects of climate change, such as exactly how much sea-level rise or drought certain regions can expect. Researchers accept such disagreements as a normal part of scientific debate, but to a public less familiar with the ways of science, they often sound like fundamental confusion — and a very good excuse not to act.

A new guide (download it for free here) from the folks at British non-profit Sense About Science takes on uncertainty with grace, patience, and Donald Rumsfeld. In Making Sense of Uncertainty, authors Tabitha Innocent and Tracey Brown make the point that far from being “a deficiency of research,” the acknowledgement of uncertainty is the mark of “sound science” and its existence is no reason to automatically take no action.

The guide was unveiled at a conference last month for science journalists, yet its contents ought to be part of the discussion beyond the newsroom or the lab, really for anyone who’s been stymied in a conversation when the other guy cites uncertainty as making your point invalid or suggesting that as a result anything could be true. As Innocent wrote in describing the guide at the Impact of Social Sciences blog:

Discussions of uncertainty can seem esoteric, academic, and not directly relevant to everyone else. But if people are discouraged by the very idea of uncertainty, then we miss out on important discussions: about weighing up the risks and benefits of new treatments, what action to take to mitigate the impact of earthquakes, or how individuals and governments should act in response to sudden changes in temperature or sea level or the latest pandemic flu threat.

The biggest "uncertain" policy debate right now centers on climate change, but uncertainty routinely pops up whenever something science-y is on the table, from Jenny McCarthy on vaccinations to quantum mechanics. Living on the edge of coastal California, how it impacts earthquake preparation is of particular interest to me.

With the help and sound bites of 21 active scientists, plus Chairman Rumsfeld’s koan on “known unknowns,” the authors discuss both the use and abuse of uncertainty in scientific discourse, when to use precise numbers, and why the underlying question is not “Do we know everything?” but “Do we know enough?” There isn’t anything classically “new” in the guide, except the vocabulary that so often escapes us of how to argue a scientifically literate case. (One debating point I especially like: “You should ask anyone who promotes an alternative idea of what is going on to indicate the uncertainty levels in their own theory.”)

The best approach to uncertainty is pragmatism. While it is important to be alert to the possibility of ‘unknown unknowns’ – of discovering that ideas about how the world works are stronger or weaker than we realized – that possibility alone doesn’t point us towards better explanations.

At 28 pages, the guide is a little bit much to keep in your wallet next time one of those uncomfortable dialogs start up and you determine, for a change, to stand your ground rather than let it devolve into a monolog. But in its conclusion, Making Sense of Uncertainty fleshes out four salient points that can be placed on a card:

• Scientific research works on the basis that there are things we don’t know.
• Scientists don’t draw conclusions based on a single piece of evidence.
• Scientific research seeks evidence not consensus.
• Scientific research is not political, but the implications of research can be.