Another (semi)related goal is acquiring a collection of humanist and rational music that is as evocative as "religious" music, optimized for communal singing. I think Humanism and science have been kind of dragging their feet when it comes to producing inspirational artwork (or at least, they've been dragging their feet when it comes to publicizing it).

That's an interesting project. I can see two difficulties which might explain why there isn't a lot of such music. One is that lyrics at a high level of abstraction tend to not work very well, and the other is that many of the emotions associated with rationality aren't easy defaults for expressing through music.

This doesn't mean it's impossible, just that there might be some new territory to explore.

It seems the statement "I am happy" can mean one is experiencing an fleeting positive reaction to external reality or it can describe the speaker as someone who does a lot of BEING happy, who is mindful of the way the impact of positive and negative stimuli on their consciousness is integrated into their perception of the world and tries to steer the process in a way that shifts the baseline of their perceived happiness higher. One could just decide to be happy all the time and through practice achieve this, but the rationalizations required to sustain that seem, AFAIK, to have a real danger of trespassing into the deeply irrational.

I had a weird moment some years back when I realized I was personally responsible for how I actively perceive the world and that I had a surprising amount of control over it. It seemed clear that the only thing keeping me from being happy was myself and that I could change my mind about unconsciously keeping myself unhappy for most of the time. Instead I decided to perceive everything in a way that would make me feel good and just adopted a casual attitude of noticing how thoroughly nice my lot in life was more than noticing the many thing that could be better but that I could not change.

It seemed that there is no deep truth or value in the way I see the world, inasmuch I as a singular observer can believe my rationalizations about the objective fairness/goodness etc of the world, sub specie aeternitatis, are factual statements, rather it is more like a matter of taste: like preferring beef to chicken. I knew there can be objective reasons for either preference, but it seemed silly and childish that I, deprived of access to the metaphorical beef, should go through life eating chicken and complaining about it because I thought it was the right thing to do when I could just steep it in some delicous sauce and have at it. I was sick of being unhappy so I had to stop making myself unhappy and spend the time doing something better. This took a few minutes of thought and then it seemed I was grinning most of the time for over a year...

I have a few questions.

1) What's "Bayescraft"? I don't recall seeing this word elsewhere. I haven't seen a definition on LW wiki either.

2) Why do some people capitalize some words here? Like "Traditional Rationality" and whatnot.

You can believe that it leads to a 100%-always-true-in-every-possible-universe conclusion, but the strength of your belief should not be 100% itself. The difference is crucial. Good posts on this subject are How To Convince Me That 2 + 2 = 3 and Infinite Certainty. (The followup, 0 And 1 Are Not Probabilities, is a worthwhile explanation of the mathematical reasons that this is the case.)

How do Bayesians look at formal proofs in formal specifications? Do they believe "100%" in them?

Yes, absolutely. The former path (working or contracting for many small companies) is the one I'd heartily recommend to novices. The latter path... scares me.