Fallibility of Consensus

I think it’s ludicrous to claim that scientific consensus constitutes scientific fraud, as Crichton alleges and as many people have echoed. In fact, I believe that consensus is how science operates; ultimately it is a flawed social process that tends to reveal truth.

The circumstances under which the consensus process succeeds or fails are very important, and are not at all easy to investigate.

The social momentum of a given academic community can deflect progress. I had hoped this would be increasingly rare, but perhaps it isn’t. It may depend to a large extent on the health of the scientific culture.

I had a brush with a minor example of this myself. It happens that my thesis advisor, John R. Anderson (tellingly, now at Pixar) recommended a topic for me where I would disprove the common wisdom about a relatively obscure atmospheric phenomenon, called the Madden-Julian oscillation. I never quite understood what John was going on about, to be honest, so it was problematic right there, though he convinced me that the prevailing wisdom had to be wrong. However, nobody except those who have already published cares enough about the MJO to care very much about an alternative hypothesis. So this would be a bad career move, even if John is right (as he tends to be about such matters). It would make a few enemies and no friends. I moved on. John’s hypothesis remains published only as grey literature from Colorado State. Does it matter? Mostly as an instance; the consensus is sticky on matters of limited importance.

The New York Times has an interesting article by John Tierney, subtitled “A Severe Case of Mistaken Consensus” on this matter, claiming that the relevance of a high-fat diet to heart disease, long held as a consensus in the US, is uncertain. I am having some difficulty judging the quality of the article or of the truth of the matter at hand.

In the discussion area, Tierney’s readers are, unsurprisingly, quick to bring up “Al Gore” (the new word for “Global Warming” apparently). Unsurprisingly, given the vagueness of Teirney’s reporting, some or unconvinced of the point being made.

To be fair to Tierney, the point is Gary Taubes’ (no relation) point, which he is making in the book Good Calories, Bad Calories, which Tierney is reviewing.

On the other hand, one commenter mentions Tierney in the same breath as Easterbrook, which is perhaps unfair guilt by association, but worth considering:

Have Tierney, Gregg Easterbrook, and John Stossel ever been seen in the same place as the same time?

They all seem to pay their bills by claiming that they know more about science than the overwhelming majority of scientists. They are journalists, and not very good journalists, at that.

Outrageous, undefendable strawmen and the appeal to an oddjob, outspoken authority are their stock in trade.

Regardless, the article does discuss the dynamics of incorrect consensus very effectively and is worth a read on that account.

Please don’t misunderstand. Consensus itself is not a sign of science misfiring. I am acknowledging that consensus is not a sign of science working correctly either. It’s more subtle than that, unfortunately.

And regarding Taubes’ point, it’s certainly argued that he suffers from the same selectivity of evidence that other consensus-busters are prone to.

As for myself, I was influenced by Taubes’ article in the Times a few years ago to take up very low carbohydrate dieting. I lost some weight episodically but in the end it was just an oscillation. And a few weeks ago I had a kidney stone episode. The doctors were puzzled because they claimed I was rather older than a typical first onset of this problem. It’s associated with excessive animal protein. So I am regrouping. Count me as one anecdotal argument against Atkins, though.

All the same, the arguments against consensus have some cogency.

Economists have a number of consensus opinions, including that theirs is the only science that is qualified to synthesize all other sciences for the policy sector. The fact that some belief is a consensus in some academic community doesn’t make it true.

Let me make sure this is clear.

  1. I think the IPCC WG1 report does represent a consensus position among the relevant sciences.
  2. I think the IPCC WG1 report is a good representation of truth.
  3. IPCC report represents truth not because there is consensus. Consensus exists because of the same intellectual and social robustness of the relevant disciplines that allows them to approach truth.
  4. The extent of the robustness of a scientific community is difficult for outsiders to determine.
  5. Yet that determination is crucial to successful governance.

Meanhile I’m still fat and we’re still building coal plants…