AMMDI is an open-notebook hypertext writing experiment, authored by Mike Travers aka mtraven. It's a work in progress and some parts are more polished than others. Comments welcome! More.
I really defer to Meaningness on this subject. He has seriously studied it, from many angles. His stuff on Kegan stage theory. metarationality is his current main slogan. He is lifelong Buddhist, and one view of meditation (probably a bad one) is that it is a process of going meta. You observe yourself, or the processes that compose yourself, including the process of observation. It's very meta except meta suggests thought about thought, whereas meditation is definitely not that, it's kind of the opposite, of learning to tamp down all that narcissistic monkeymind reflexivity.
One question: is going meta a skill that can be taught, or perhaps a large set of skills, different for different concrete levels of meta (that is the Kegan view as I understand it). There are people who can help you do this, it's something you can and should talk about. On this Chapman and the Rationalists are very aligned, which somehow surprises me.
My own divergent view – metaness is just something that just goes on all the time, it doesn't require special qualifications, everybody is going meta all the time, its a human thing. We don't have stages, which sound suspiciously like promotions in some organizational hierarchy. Or suggests the snobs view that only the elite are fully conscious human beings, and most people are dull-witted cattle who lack the self-awareness of the educated, the trained, the elite.
Ah yes reminds me of The Boy Scouts, you get ranks like in the army, achievement badges which you wear with perfectly normal pride.
But, we can get better, some people get better than others, and let's assume that part of being a high stage is being aware of all the low-stage stuff going on.
Mostly we get this through drama – that found in formal narratives like movies and myths, but also the daily drama of socialization, where people put forth their personas and do impro with them..
Going meta is a fundamental act of computer system design. Not one usually addressed head on. Design of Design might be an exception. Sort of part of procedural thinking/GOFAI, although that emphasizes different aspects I think. "Thinking about thinking".
Lisp is a metalanguage, nobody seems to quite grasp that.
Clojure (which has macros but somehow almost never needs them) is less meta in that way.