So please, teach me.
I can give pointers. Your initial set of assumptions and reasoning is very close to that of Descartes' Meditations (I linked to that earlier), so I presumed you were familiar with his work. However, he continues his line of reasoning to "prove" that God exists, hence the joke. Since your line of thought agrees with his, you might want to read him.
You could do the whole "correct" path of Socrates, Plato, Aristotle, Roman Sceptics, etc etc, but although some are enlightening (especially the sceptics should appeal to the cynics), it can be dry at times. Personally, I totally dig Kierkegaard, for instance. He rocks. And Socrates is awesome, too. He's like the Big Daddy of Philosophy.
To put it differently: There's a big difference between having humility and learning about existing ideas before thinking you have everything figured out, and taking famous work on faith or not questioning it, or making assumptions either way about how "smart" it is.
Oh, but I never said you shouldn't question it, I agree that you should. I once wrote a paper on Descartes' Meditations II and III, pointing out the errors in his way of thinking (I don't know how good it was, I flunked out of uni before it got graded). That doesn't make me smarter than him, I've got access to knowledge of those who came after him. But to question it, you need to read it first.
Also, philosophers are never popular. Maybe they had groupies and fanclubs in ancient Greece or Rome, but not since then. They're famous because other people say they are, and those other people are generally more knowledgeable than I am. So it's at least an indication that their work is worth reading. It isn't always, there's a lot of crap around, but you never know until you read it.
[rant at Joe the plumber (or Henk and Ingrid, as he's called here)]
It's a sign of the times, I guess. Freedom of speech and all. There were times when people knew when to shut up. Nowadays, the opinion of the common man weighs as much as the opinion of the learned man, because even they can be wrong. Yes they can be, but overall they're a lot less wrong than you, common man. So please, don't speak up for yourself, and when you do, make sure you put a lot of thought into it. And even then, test it first against someone who knows his shit before spouting it in public. You're embarrassing the human race. Shut up.
[/rant]