Science is NOT done by consensus...
A nice article in the Financial Times...
Numbers are critical to democracy, but science is not a democracy. If an evangelical Christian converted all members of the Royal Society to creationism, that neither would nor should affect my belief in evolution. Most scientists know no more about climate change, HIV/Aids or the measles, mumps and rubella (MMR) vaccine than do most lawyers, philosophers or economists, and it is not obvious who is better equipped to assess conflicting claims on these issues. Science is a matter of evidence, not what a majority of scientists think.
It is easy to see why the president of the Royal Society might want to elide that distinction, but in doing so he turns the organisation from a learned society into a trade union. Peer review is a valuable part of the apparatus of scholarship, but carries a danger of establishing self-referential clubs that promote each other’s work.
Statements about the world derive their value from the facts and arguments that support them, not from the status and qualifications of the people who assert them. Evidence versus authority was the issue on which Galileo challenged the church. The modern world exists because Galileo won.
But to use the achievements of science to assert the authority of scientists undermines that very process of science. When consumers believe that genetically modified foods are unsafe, mothers intuit that their children’s autism is caused by the MMR vaccine and politicians assert that HIV/Aids is a first world conspiracy, the answer that the scientific consensus is otherwise does not convince – nor should it. Such claims are mistaken because there is no evidence for them, not because scientists take a different view: scientists should influence policy by explaining facts and arguments, not by parading their doctorates.
The notion of a monolithic “science”, meaning what scientists say, is pernicious and the notion of “scientific consensus” actively so. The route to knowledge is transparency in disagreement and openness in debate. The route to truth is the pluralist expression of conflicting views in which, often not as quickly as we might like, good ideas drive out bad. There is no room in this process for any notion of “scientific consensus”.