I Want To Believe: Rational Edition

Trying to "convince" yourself is doing it wrong. Say it out loud, say it to yourself (and avoid saying the opposite to yourself), and perform the external actions that someone normally does who believes it.

This is how people get "belief in belief" even when it is contrary to their evidence, and it works.

The lower my estimated probability that the self-fulfilling prophecy will work for me, the less able I am to use the self-fulfilling prophecy as a tool, even if the estimated gains from the bet are large. How might I deal with this problem, specifically?

By not using doublethink? I know you didn't want that questioned, but I'm going to call it into question by suggesting a different method, by illustrative example from personal experience.

The first time I considered doing a hundred-mile bicycle ride, once I had made the assessment that I could do it (I had never ridden further than 50 miles in one day before), I did not concern myself thereafter with wondering about the matter. That would be wasted motion: something which, predictably at the time you think it, will afterwards be seen to have contributed nothing to the task at hand. I had made a decision, I signed up for the event, I undertook what practice I judged useful, I turned up on the day, I completed the course. Belief that I could do it did not enter into the matter after that initial decision.

The key word is intention. This might be something similar to, or an instance of, what Brienne calls a "mental posture". It's something you do with your mind, not a proposition you believe. Decision screens off belief from action.

In these situations people naturally use selection bias. Make a list of all similar situations where you achieved some success in something similar to the upcoming competition. With a bottom line "...therefore, I will win this competition, too".

Write it on a paper, put it on your bedroom door, read it every morning then you wake up. Try to re-live (imagine in "near mode") the situations mentioned on the paper, and then when you are in the right mood, imagine the victory in this competition. (How would it feel like, for your senses? What would you see? What would you hear?) Then have a small exercise, or do something that at least symbolically contributes to your victory.

It sounds like you're talking about convincing System 1 of something, or forming an "alief": http://agentyduck.blogspot.com/2014/06/growth-mindset-forest-system-1.html

Read more things that agree with what you want to believe. Avoid content that disagrees with it or criticizes it.

Start with an intermediate step, beliefs whose truth value depends on whether you believe in them such as placebo effects, social confidence strategies, and relaxation techniques.

It's causing me significant difficulties in my personal life.

What kind of difficulties?

The skill you are trying to cultivate is good for things like lying, manipulation, and bluffing, but not particularly helpful for social anxiety. Lying and bluffing in social situations is an advanced level social skill, not beginner level. At the beginner level you just want to treat it like it's a scary spider - gradually up your exposure until you feel comfortable.

Since you want an answer though - it's a game, a play, an act. Purposefully pretending and taking on roles is more effective than attempting to lie to yourself.

I don't think I can actually lie to myself on purpose about propositional statements, but emotions aren't propositional statements, you don't really have to lie to yourself to feel emotions that you wouldn't normally feel.

I can't tell, from your post, what kind of propositions you are trying to convince yourself of. If it's an attempt to win competitions, then you're putting your effort in the wrong place. Whether you win any given competition is largely going to be determined by who else shows up to compete. Improving your chances means reducing the number of people who can reliably beat you, and that only happens through research and practice (since murdering competitors is generally seen as bad sportsmanship).

Other than that, it sounds like you've discovered the flaw in Pascal's original wager (well, one of its flaws anyway). You can decide it's rational to believe something, but actually believing it is a different matter. In religion, actual belief is key, and therefore Pascal's wager isn't going to make a lot of true converts, even though it's a beautiful piece of reasoning.

I am having a similar issue, and am currently dealing with it by developing better acting skills. As long as I do and say things consistent with the belief set I wish I had (and don't), my ends are achieved regardless of whether I actually hold that belief set. This may or may not be applicable to your situation.

I think there's a limit to how much a belief like this can be instrumental. It's a belief whose benefit would be very highly context dependent. For example, believing that you are capable of winning a boxing match might be highly instrumental when you're actually in the ring, but it would not be instrumental before the match when you're deciding how much money you want to bet on your performance in the competition (since you would bet as if your likelihood of winning was higher than it actually is).

That said, I think that psychologically dealing with high-stress situations is a skill just like any other. You practice, you fuck up, you think about it, and eventually you get better.

If believing that I am capable of winning a competition will cause me to win, believing that I am capable of winning is rational

Self-confidence will only help you in games where other factors already favor you. Unfounded self-confidence (or any unfounded belief) is very harmful.