I'm not trying to argument by consensus. I'm saying "look, the researchers in this field are saying..." Why so much people thinks he knows more about a subject than the researchers?
10 years ago if I had a stomach ulcer, all the researchers and doctors would have told me I had stress and that is what caused it. They would have prescribed me treatments and told me to change my behaviours, which would have all been ineffective.
Two researchers thought outside the box, went against the consensus, ignored what all the researchers said, and proved that stomach ulcers were caused by a bacteria. An entire industry and field was turned upside down, and Nobel Prizes were handed out.
What's my point? You can never tell when research is right or wrong, so you must always be sceptical, and never say 'the science is settled, because there is a consensus'. You can never rely on the word of researchers, only on the proof that they have or have not generated.
Edit : I re-read the parent, which goes like this: >"Unfortunately, in this case there is a correlation: "In the scientific literature, there is a strong consensus that global surface temperatures have increased in recent decades and that the trend is caused primarily by human-induced emissions of greenhouse gases"
I read this statement as saying correlation is proven by consensus - which is wrong no matter what the topic.
The reason 'healers' are wrong about mental illness is because their hyphotheses are either untested, or proven to be wrong. Not because lots of researchers agree with the opposite.
The 'ordinariness' of a person is immaterial - Einstein was a patent clerk who had a book published refuting his views by 100 experts. He was still right.
The point I am making here is that you should never argue a point by consensus, or by authority, for that matter. You should argue a point based on the results of testing a hypothesis and finding it true or false.
Scientists of any discipline do not become automatically right because they don a white cloak and publish in a journal - not when one does it, not when an entire industry does it. It is a fundamental mistake to believe in an argument from authority or an argument from consensus. Quite frequently, authorities do get it right (precisely because they have studied it for a long time), and most of the time, they all agree with each other (forming a consensus). But these things flow from the fact that something is right (and observable, and reproduceable) - not the other way around.
I say this to try and elevate the level of debate quite apart from climate science, or GMO, or any of the other fashionable arguments.