| That's exactly what almost all knowledge is. When was it that you last verified something by yourself, with an experiment? You didn't test the things you know. You know things because you could see they were the consensus, and so you had no reason to challenge them. If an idea is disputed, then you trust it less. If it comes from a small number of reputable sources, then you trust it more than a large numbers of unreliable people. So with the Wiki. Human knowledge isn't from the platonic realm. Human knowledge isn't checked by a theorem prover. You get almost all of your knowledge from other people, and you have no choice but to trust them for almost all of it. |
That's what almost all human assumption and belief system is, also ideology and religion, but knowledge is indeed something different, and not of a type that should rely on democratic consensus. It instead needs to be held up by material evidence that's always subject to retesting no matter how unpopular a new idea is. This is obvious.
The rest of what you say could just as easily be applied to the foolish social dogmas of nearly any past age in human history, dogmas that so often turned out to be wrong. A small number of reputable sources (for their time) upheld doctrines such as geocentrism, religious extremism, hatred for certain racial groups and numerous fervent beliefs in the right of certain people to dominate others. These are just a few examples.
A more material one would be the certainty among reputable sources that plate tectonics were nonsense, until of course they were shown not to be by what started as an argument by only a few people who were deemed very unreliable.
None of this is to give weight to every crackpot idea put forth, or claim that all opinions are equally valid until stated otherwise, but what makes the difference is evidence, not consensus.