Ochi reason number one...

[Mark]

For instance, a color blind person would still find that a spectrograph of the sky shows a peak in the short visible (i.e., "blue") end of the spectrum.

Perhaps a bad example, but then truth is dependent upon the quality of the measure, a spectrograph as opposed to the eyes. Therefore if I am of the extreme opinion that the sky is not blue, I simply have to disagree with the idea that the short end of the visible spectrum is in fact blue. Whatever proof offered that the sky is blue will not convince me because, due to my extremism, I simply refute everything. This trivial example demonstrates what happens in politics, often punctuated by people saying, "There's no way to convince these/those people. They have an answer to everything." Which then leads to the statement "We'll have to agree to disagree." Blah

A person's perception of truth may be flawed. But there are matters of fact and matters of evidence and, insofar as they exist at all matters of fact are either true or they aren't. Many people, made more ignorant by exposure to a "liberal arts" education and taught by people more ignorant than themselves apply the relative truth of opinions to the absolute truth of facts.

Your statement then begs the question: How many flawed perceptions does it take before it becomes truth? I'm not so foolish as to believe that everything is relative, that line of thinking soon degenerates into nihilism. I'm just pointing out when ideas are less obvious than the color of the sky, the problem of finding the real truth becomes even more difficult. We have to start defining everything, and soon apathy sets in. As in our previous example, a definition of the term, blue, is required by both sides of the argument.

As to the fence sitters: there is a fine difference between moderation and apathy. And, all too often, the first is used as a justification for the second. If you believe in nothing, if you care for nothing, then you will influence nothing and you will accomplish nothing. If it is your desire to do so, then you are a moderate. If you just let it happen, then you are apathetic.

I don't see the relationship between moderation and apathy. Moderation seems to be an attempt to maintain a sense of balance. Apathy would be no attempt at fomenting any opinion at all, and as you say accomplish nothing. I do not see how moderate's 'desire' is to accomplish nothing. Maybe I'm missing something there.

But the truth, in matters of fact and often in matters of opinion, is not found at the geometric mean of the arguments. The world is not 1% flat and 99% round because that's the ratio of beliefs.

Agreed. Truth, requires a definition. It seems that some believe that truth is a majority opinion. I would put forward that truth is only attainable when everyone observes the same event in the same way, which can never happen. The only truth then would be individual in nature. In that case, the sky is blue...to me.

Thanks for the response, Pete. Insightful.