When I read the original quote, I noted the conspicuous absence of any kind of positive assertion that the speaker is immune from those problems, and I read it as cautioning us against thinking that we are not similarly wrong about some of those very problems and other important problems that we are blind to.
Did you read it in the context of the atheist blog post Eliezer linked to? I agree that the quote was possibly meant to be cautionary, but I think it was primarily meant to show that believing in things 200 years old is generally not a good idea. Maybe I misunderstood the point of the post, though; the cautionary value is a more useful interpretation for us aspiring rationalists, and 'don't put faith in ancient wisdom' is rather simple advice by comparison. Because of that, context be damned (even if I did interpret it as was meant), I'm going to switch to your interpretation. :)
A monthly thread for posting rationality-related quotes you've seen recently (or had stored in your quotesfile for ages).