Scientific consensus
Personal Essay
It is impossible for any of us – as human individuals – to always be capable of using logic to arrive at the correct conclusion from all of the evidence available.
We live a society where we are dealing with what amounts to an information tsunami -- and, worse, where there are individuals who stand to gain tremendously by encouraging misunderstandings.
There is no given human being who has the capacity to understand all of science (where "science" here is a stand-in for something like "the best understandings achieved and documented regarding the laws of nature and their practical consequences"); I think that had become essentially impossible by the 1800s, possibly much earlier.
I think you know that I'm never one to say "trust the experts!" (that would, after all, be advocating a form of unaccountable power) -- but unfortunately, we find that we must increasingly do so, since we as individuals cannot possibly become instant experts in any field, even with the resources of the internet.
It seems to me, then, that what we must resort to is "trust, but verify".
We check the logical points we can check; we examine each expert (individual or organization) for signs of dishonesty or bias; we look for evidence of diligence (or sloppiness) in their methods. If an expert has been known to use questionable logic in proceeding from premises to conclusion, we tend not to trust that scientist's other analyses; where the analysis involved matters beyond our understanding, we must look to others in the same field for verification -- but there are always points we can check: does this criticism follow logically from the premises? Are their premises in alignment with accepted reality, or are they smuggling in conclusions disguised as evidence?
The "scientific consensus", as I see it, derives from the conclusions who have done well on all of these counts: we have no reason to doubt their diligence, their logic, their reasoning, or their understanding of established fact. When we check the logic of their arguments -- both their primary assertions and their responses to criticism -- what are the flags we see? Is the arguer diligent, logical, and honest? Do they acknowledge those times when they did in fact make mistakes (as everyone does, sooner or later), and revise their arguments to be in accordance with those corrections?
Those are the things we need to look at, when deciding who is being honest and who is privately motivated in choosing the beliefs they choose to endorse.