Naomi Oreskes: On Scientific Knowledge

Merchants of Doubt by Naomi Oreskes and Erik Conway tells the story of "how a handful of scientists obscured the truth on issues from tobacco smoke to global warming."

The book has received a lot of attention, and this video convinced me to read it.

The protagonists of our story merchandise doubt because they realize … that doubt-mongering works. And it works in part because we have an erroneous view of science. We think that science provides certainty. And if we lack certainty, we think that something is wrong with the science.

This view that science could provide certainty is an old one, but it was most clearly articulated by the late 19th-century positivists, who help out a dream of a positive knowledge, in the familiar sense of absolutely, positively true. But if we've learned anything since the 19th century, it's that the positivists' dream was exactly that, a dream.

History shows us clearly that science does not provide certainty. It does not provide truth. What it provides us with is the consensus of experts, based on the organized accumulation and scrutiny of evidence.

Hearing both sides of an issue makes sense when debating politics in a two-party system. But there is a problem when its applied to science. When a scientific question is unanswered, there may be three, four, or a dozen competing hypotheses, which are then investigated through research. Or there may be just one generally accepted working hypothesis, but with several important variations or differences in emphasis. …

Research does not provide truth, what it provides is evidence, and in time that evidence may settle the question. … After that point, there are no sides, there is simply accepted scientific knowledge. There may still, of course, be questions that remain unanswered, to which scientists turn their attention. But for the question that has been answered, … there is simply the consensus of expert opinion. That is what scientific knowledge is. …

Yet most of us don't understand this. If we read an article in the newspaper presenting two opposing viewpoints, we tend to assume that they both have some validity. And we tend to think it would be wrong to shut one side down. But often one side is represented by a single, quote, expert. Or, as we saw in our story, one, or two, or maybe three. … And often those so-called experts are not, in fact, experts at all. …

When it came to global warming, we saw how the views of Sykes, Nierenberg, Singer, and a handful of others, who were not climate scientists, … were juxtaposed against the collective wisdom of the entire Intergovernmental Panel on Climate Change, an organization that encompassed the work and views of thousands of climate scientists around the globe, men and women of diverse nationality, temperament, and political persuasion.

And this leads to another important point, that modern science is a collective enterprise. … From its earliest days, science has been associated with institutions. … Because scholars understood that to create new knowledge, they needed a means to test each others' claims. … Until a claim passes the judgment of one's peers - that is, peer review - a claim is only that, just a claim. What counts as knowledge are ideas that are accepted by the society of experts.

See also Harry Collins and Robert Evans on "Expertise in the Age of Amateurs" and Brian Wynne on "Climate Scientism and Public Policy."

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