It was something of an exaggeration. I'm capable of doing many things that realistically, I'm not going to bother with.
But I don't think "clear thinking" is a solution to this problem. I can read a book and say "the facts as presented don't fit the narrative", which is what I did with paulsutter.
If I'm really dedicated, I can look up references. I can bypass the paywall, read a journal article, and see that the author has misrepresented the results.
But I can't read a book and say "wait, you're completely ignoring the effect that in-fighting in the Roman senate had on politics in Britain circa A.D. 50", because I don't know anything about that subject. I don't even know that it's relevant. Unknown unknowns.
I can't know everything, so I have to rely on other people.
That, my friend, is a skill you can acquire and grow.
Since we're on the topic of popular science books, here's a reasonable read that can help you start improving:
http://www.amazon.com/Art-Thinking-Clearly-Rolf-Dobelli/dp/0...