Is the purpose of education to expose us to the greatest number of possibilities existing in a universe of diverse thinkers, or is it to be funnelled into a choking paucity of rigid thought patterns, much as rainwater running down a gutter has no other way to go...?
No. The purpose of education is to produce educated, cultured individuals - "culture" in the Matthew Arnold sense of "the best which has been thought and said". Not all "possibilities" - viewpoints, opinions, theories, whatever - are valuable or worthwhile, and so should be eliminated. I am a conservative, so I am expected to say horribly elitist, anti-egalitarian things like this, and worse, I really believe it. YMMV.
Given these two choices, I'll take the latter. My children will be exposed to the massive universe of cheap, stupid ideas you don't need expensive intellectual undergirdings to understand for free.