Knowledge is great: I suspect we can agree there. Sadly, though, we can't guarantee ourselves infinite time in which to learn everything eventually, and in the meantime, there are plenty of situations where having irrelevant knowledge instead of more instrumentally useful knowledge can be decidedly suboptimal. Therefore, there's good reason to work out what facts we'll need to deploy and give special priority to learning those facts. There's nothing intrinsically more interesting or valuable about the knowledge that the capital of the United States is Washington, D.C. than there is about the knowledge that the capital of Bali is Denpasar, but unless you live or spend a lot of time in Indonesia, the latter knowledge will be less likely to come up.
It seems the same is true of procedural knowledge (with the quirk that it's easier to deliberately put yourself in situations where you use whatever procedural knowledge you have than it is to arrange to need to know the capital of Bali.) If your procedural knowledge is useful, and also difficult to obtain or unpopular to practice or both, you might even turn it into a career (or save money that you would have spent hiring people who have).
Rationality is sort of the ur-procedure, but after a certain point - the point where you're no longer buying into supernaturalist superstition, begging for a Darwin Award, or falling for cheap scams - its marginal practical value diminishes. Practicing rationality as an art is fun and there's some chance it'll yield a high return, but evolution (genetic and memetic) didn't do that bad of a job on us: we enter adulthood with an arsenal of heuristics that are mostly good enough. A little patching of the worst leaks, some bailing of bilge that got in early on, and you have a serviceable brain-yacht. (Sound of metaphor straining.)
So when you want to spend time on learning or honing a skill, it makes sense to choose skills with a high return on investment, be it in terms of fun, resources, the goodwill of others, insurance against emergency, or other valuable results. Note that if you learned a skill, used it to learn a non-customized fact, and do not anticipate using the skill again, it's not the skill that was useful; the skill was just a sine qua non for the useful fact, and others don't have to duplicate the research process to benefit. A skill that yielded one (or more) customized facts - i.e., facts about yourself, that you can't go on to share straight up with other people - might be a useful skill in this way, however.
For practical daily purposes, what is your most valuable skill (or what most valuable skill are you trying to attain now)? Post it in the comments, along with what makes your skill valuable, tips for picking it up, and what made you first investigate it.
Because I want to be right, I love to be wrong. Or more correctly, to realize why I'm wrong. I'm not sure how it came about, my best guess is it has something to do with humor, but every time I realize I'm wrong, I get happy. It gives me a stupid grin across my face and makes me snicker. It also happens when I realize why someone else is wrong. (as in becoming aware of what mistake they have made, or what information they are missing - not just that they are mistaken!)
Sure, most people want to be right, but they hate to be wrong. They get ashamed, frustrated, blame themselves, and try to avoid it. The problem, I believe, is that they have bundled "being wrong" together with realizing that they're wrong. To avoid these feelings, they unconsciously try to avoid giving up on their beliefs for as long as they can get away with it.
If you want to be right then you should love realizing that you're wrong, because every time you do, you'll get more right.
In short, I guess you would call this skill "being able to update". Just wanted to give my theory of how it works for me, and why so many are bad at it. The reason behind why most people have this faulty behavior is most likely the pursuit of status. Groups don't reward ability to update, in fact they punish it. You lose prestige, they'll call you a flip-flopper, instead of praising your ability to discard false knowledge. Which explains a lot about the state of the world and it's leaders, really!