Well, nobody here has challenged my belief/assertion/bit of philosophy about justification and truth: I think that truth is irrelevant to justification. It seems clear that historical (Pre-Kantian) methods have failed to produce a current consensus that any justification is adequate in theory or in practice to produce objective certainty about anybody's perspectives on philosophical questions. Neither have post-Kantian methods.
To me (and the experts I got this idea from) the idea 'certainty' reflects more confidence in linguistic representation than is warranted. Of course I'm not telling the absolute truth about this, and I don't believe that we could. If there's any philosophy which produces a different but equally reasonable perspective on this, I haven't heard it...yet.
I understand (uncertainly, of course) why many people are so very reluctant to share their experience on how strongly we ought to be attached to our beliefs.
The discussion of my question about fallibilism seemed to have produced a reasonable consensus of what the relatively brave commenters said:
“Given Hetherinton's description of fallibilism, absolute certainty is no longer an option…There are no indisputable truths coming.”
“I think the general consensus [in philosophy!] is that language simply isn't up to the task of establishing absolute certainty”
“It is hard to imagine an "ultimate" argument pro- or con- some philosophical point of view... Obviously, "people believing in absolute truths" are not interested "to appreciate alternative perspectives" with respect to truth, because, if alternative, they are false.”
One commenter believes that “a large percentage of contemporary professional philosophers do not accept postmodernism (on just about any definition of postmodern).” Yet the notion “postmodern” has no true definition and that comment never defined the concept, which has been widely applied in many ways, and that person didn’t address any philosophy. I refer to post-modern or post-Kantian philosophy "objectively" (that is according to this linguistic definition) as books and articles published by professional philosophers since Kant's work was published.
I’m gratified that these few people have thoughtfully considered the issue which has brought me such disfavour from people who are (perhaps mistakenly) opposed to the notion that no assertion or belief about philosophy is appropriately or correctly to be considered as absolutely true.
I think that all of us have believed in the past that we could and did know the truth about what we learned; some of us have since transformed our views to fit current philosophical and psychological models of linguistic representation, justification, cognition, and comprehension. I don't believe that my beliefs on any of these matters could possibly be completely true; that leaves me room to accommodate better ideas.