Academics like to say that we teach "critical thinking" without thinking too critically about what it means to think critically.
Being Critical, Not Thinking Critically
Too often in practice, people equate critical thinking with merely being skeptical of whatever they hear. Or they will interpret it to mean that, when confronted with someone who says something that they disagree with, they either:
a) stop listening (and perhaps then start shouting),
b) find a way to squeeze the statement into our pre-existing belief system (if we can't we stop thinking about it), or
c) attempt to "educate" the speaker about why their statement or belief system is flawed. When this inevitably fails we stop speaking to them, at least about the subject in question.
Ultimately, each of these responses leaves us exactly where we started, and indeed stunts our intellectual growth. I confess that I do a, b, and c far too often (except I don't really shout that much).
To me, critical thinking means, at a minimum, questioning a belief system (especially my own) by locating the premises underlying a statement or conclusion, whether we agree with it or not, and asking:
1) whether or not the thinker's conclusions follow from those premises,
2) whether or not those premises are "reasonable," or
3) whether or not what I consider reasonable is "reasonable" and so on.
This exercise ranges from hard to excruciatingly uncomfortable – at least when it comes to examining my own beliefs. (I’ve found that if I dislike a particular conclusion it’s hard to get myself to rigorously follow this procedure; but if I like a conclusion it’s often even harder.)
Teaching Critical Thinking
Fortunately, people have written articles and books that offer good criticisms of most of my current beliefs. Of course, it's then up to me to read them, which I don't do often enough. And so, unfortunately, I don't think critically as much as I should...except when I teach economics.
It’s very important, for example, for a student to critically question her teacher, but that’s radically different from arguing merely to win. Critical thinking is argument for the sake of better understanding, and if you do it right, there are no losers, only winners.
Economics does a pretty good job of teaching critical thinking.
Once in a while, a student speaks up in class and catches me in a contradiction – perhaps I’ve confused absolute advantage with comparative advantage – and that’s an excellent application of genuine critical thinking. As a result we’re both now thinking more clearly. But when a student or colleague begins a statement with something like “Well, you’re entitled to your opinion, but I believe…” that person may be trying to be critical (of me) but not in (or of) their thinking.
It may not be the best discipline for this, but I believe economics does a pretty good job of teaching critical thinking in the sense of #1 (logical thinking). Good teachers of economics will also strategically address #2 (evaluating assumptions), especially if they know something about the history of economic ideas.
Economics teachers with a philosophical bent will sometimes address #3 but only rarely (otherwise they'd be trading off too much economic content for epistemology). In any case, I don't think it's possible to "get to the bottom" of what is "reasonable reasonableness" and so on because what ultimately is reasonable may, for logical or practical reasons, always lie beyond our grasp.
I could be wrong about that or indeed any of this. But I do know that critical thinking is a pain in the neck. And that I hope is a step in the right direction.