The Litany of Tarski (formulated by Eliezer, not Tarski) reads
If the box contains a diamond,
I desire to believe that the box contains a diamond;
If the box does not contain a diamond,
I desire to believe that the box does not contain a diamond;
Let me not become attached to beliefs I may not want.
This works for a physical realist, but I have been feeling uncomfortable with it for some time now. So I have decided to reformulate it in a more instrumental way, replacing existential statements with testable predictions. I had to find a new name for it, so I call it the Litany of Instrumentarski:
If believing that there is a diamond in the box lets me find the diamond in the box,
I desire to believe that there is a diamond in the box;
If believing that there is a diamond in the box leaves me with an empty box,
I desire to believe that there is no diamond in the box;
Let me not become attached to inaccurate beliefs.
Posting it here in a hope that someone else also finds it more palatable and unassuming than straight-up realism.
EDIT: It seems to me that this modification also guides you to straight-up one-box on Newcomb, where the original one is mired in the EDT vs CDT issues.
EDIT2: Looks like the above version resulting in people confusing desiring accurate beliefs with desiring diamonds. It's about accurate accounting, not about utility of a certain form of crystallized carbon.
Maybe the first line should be modified to something like "If I later find a diamond in the box...", or something. How about the following?
If I will find a diamond in the box,
I desire to believe that I will find a diamond in the box;
If I will find no diamond in the box,
I desire to believe that I will find no diamond in the box;
Let me not become attached to inaccurate beliefs.
For some reason the editor does not let me use the <strike> tag to cross out the previous version, not sure how to work around it.
I was expecting to find someone commenting about beliefs whose truth-value may be hard to know but whose effect is positive nonetheless. Several examples (which I don't necessarily personally endorse)
If believing this homeopathic sugar pill works will make it work,
I desire to believe that this sugar pill works.
If believing this homeopathic sugar pill works will not make it work,
I desire to believe that this sugar pill does not work.
Let me not become attached to beliefs that do not serve me.
or
If believing in synchronicities will cause more good things to happen in my life,
I desire to believe in synchronicities.
If believing in synchronicities will not cause more good things to happen in my life,
I desire to not believe in synchronicities.
Let me not become attached to beliefs I do not want.
It appears that, if you have the ability to actually self-modify your beliefs as such, the "Litany of Instrumentarski" could be a useful way to deal with the thing where rationality breaks things like the placebo effect. Sugar pills, or whatever, if you can adopt the positive sides of beliefs that are self-fulfilling prophecies (true either way you believe them, like e.g. the Pygmalion effect) then that ought to be conducive to winning.
What's 'accuracy' without 'reality'?