The vast majority of people who confidently hold forth on, say, the existence of gluons, or the expansion of the universe, or the various evidences for evolution, or the proposition that light is both a wave and a particle are entirely reciting hearsay they picked up from some Authority on the Discovery Channel or Popular Science.
In other words, they are behaving exactly like adherents of a religious system.
Whatever politically-driven "scientific knowledge" that the media pushes, I tend to not treat as dogma.
It could be true. It could also be not be true, and most people don't know any better.
Being educated in one special history-- I know that ordinary people typically have a superficial knowledge of any given field because people have a superficial knowledge of history. It's not that they're stupid, it's that they have other things to do. I passed high school science, and I have a passing interest in science, but don't ask me to comment on any scientific issue (with the major exception of pregnancy and fetuses on which I do read quite a bit.) I know enough to know that I don't know. I'm probably more scientifically literate than average (which is not saying much, so I'm not bragging) but I know that it takes a lot of investigation to truly come up with an independent opinion on any subject (instead of just relying on the authority of books and encyclopedias) and I just don't have time to learn everything, so I simply remain with no firm opinion on a number of questions.
But the media love an agenda, they love conflict, and they're liberally biased, so they tend to push scientific agendas. When political issues are dependent on scientific knowledge, it's not enough to depend on authority. A lot of people rely on what the experts say, and go with that momentum. That's not a very logical manner to proceed.
Politically, though, it can be an uphill battle to go where the facts lead you, because you often swim against the current.
Scientific information is also often "packaged" and when you unravel that package, there are lots of omitted details and points that go against the political agenda of the day.
So I don't get excited about a lot of scientific controversies. I know there's more to it than what is said in the media, but who has time to read beyond the headlines? Journalists tend to stick to the predominating narrative anyway. You really have to go to academic sources yourself to get the real story.
UPDATE
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