Criticism. We all know it – to a great extent it’s a hallmark of our being rational people. But although as rational people we should use criticism as part of critical thinking, it is not uncommon to find criticism viewed as an end in and of itself. The two may sound similar, but there is a fundamental difference in the ideas behind them that is often overlooked – implicitly, if not explicitly.
A bit of terminology, for my point later on: By “criticism” I mean here the sense in which we point out negatives, flaws, or mistakes in a certain idea or action (setting aside for the moment important matters like what constitutes legitimate criticism, what makes a particular criticism more or less valid, etc.). By distinction, “critical thinking” (sometimes called "critical discussion", “critical rationalism” or just “criticalism”, with minor differences) is an intellectual method in which we subject ideas – not least our own – to honest discussion and criticism, out of the hope that we may learn something constructive about, and maybe move a little closer to, what is actually the case (or what is “right”, or the “truth”, to use very loaded terms for their relatively simple and intuitive senses), or at least expose our underlying principles. In a nutshell, it's taking others' arguments – and their logical consequences – seriously.
My claim is that criticism that is not raised for the purpose of critical discussion (a) is widespread, not least where it purports to be offered precisely for that purpose; and mainly (b) achieves far less than what most critics seem to think it does. Examples of (a) abound – just skip over (or return, whichever the case my be) to Facebook, or televised debates, or parliamentary debates, and most likely you're seeing an instance of non-criticalist criticism. My assertion (b), on the other hand, may need more explanation.
No matter what position one is coming from, there is always what to criticize in light of it. The internet, in particular, provides a near-infinite world of possibilities to criticize people, ideas, acts, writing, thoughts. For a certain type of person, this kind of criticism feels great: "You're stupid/evil!" (subtext: "I'm pretty smart/righteous."). It can prove galvanizing in many an internet echo chamber: "Hey guys, check out what this idiot said!" There's no question it can help pass the time – one can literally spend a lifetime seeking out and criticizing ridiculous statements. In some rare cases it might even prevent a mistake or – very rarely – get someone thinking.
All of this is fine and good – to each their own – so long as we remember that criticism on its own says nothing about (the justification of) the critic's own position. Unfortunately, I'm quite convinced that many out there criticizing other positions for-criticizing's-sake feel, intuitively or otherwise, that in so doing they've provided a defense, justification, or corroboration for their own positions; in which case their efforts are misplaced. These notions belong to the realm of critical discussion: this is where we can try to provide arguments and defenses of a position in order to try to show it is genuinely better, and criticize other positions – but only at the (vital) "cost" of subjecting our own positions to criticism as well.
It's been argued that these kinds of debates are largely pointless, that matters of principle and/or incommensurable positions can't even begin to enter into a rational discussion, but I think that's only true if we've set our expectations too high: for instance if we expect such debates to end in full agreement. While it's true that reaching such agreement between disparate points of view is quite rare, I would argue that many honest debates of this type have made at least some small headway: clearing up some mistaken preconceptions, clarifying some misleading language that had previously lead to misunderstandings, and mainly – getting to the crux of some matters; if only clarifying more fundamentally why, or where, the sides disagree. Some limited agreement can usually be teased out, and in many instances positions are often clarified, modified, and ultimately improved as a result of this process. (This idea is hardly new, as in most important respects it's similar to the Socratic Method.)
If we apply a little critical thinking, I think it quickly becomes apparent that the (mere) fact that proponents of some or other position have performed acts, or expressed ideas, that are worthy of criticism, does not in the main add or detract from the justification of any other position*. People everywhere, at every point in time and from every point of view have said and say, and have done and do, things that are "stupid". Owing to the fact that we're all human, there will always be whom to criticize – people are fallible. We have yet to find the position, principle, or worldview that "immunizes" from this fact. The question is what we do with it.
* Unless of course, that position was "there are people who do or say things that are worthy of criticism", a rather trivial, and by now safely established point.