Okay, so the responses so far seem less than impressed with these ideas, and it has been suggested that maybe this shouldn't be so public in the first place.

Do people think I should take down this post?

use a subtle variant of these gestures to signal to other Effective Altruists who you are, without giving it away to more egoistic types.

Sorry, still not seeing it. Why are you trying to give these cryptic signals to other EAs at work? Is the idea that EAs will start cutting one another specially favourable deals and giving preference to one another for good jobs? That seems likely to be hugely counterproductive, because as soon as such things get suspected it's going to be bad for the whole EA movement.

If you're overtly signalling affiliation while making a political speech or something, why not just do it by talking about effective altruism? If it's a speech in which it doesn't make any sense to do so, then what the hell are you doing signalling affiliation in the first place? Again, this is the kind of thing that gives a movement a bad name. (Ditto, even more so, if it's covert.)

a subtle "Dark" gesture [...] a financial company

OK, so I am, let's say, an investor considering putting some money into a hedge fund. I go to visit their offices.The fund manager or one of his colleagues greets me by putting his hand behind his back and giving a thumbs-up gesture. Are you suggesting this is a subtle gesture that won't make anyone suspicious?

Again, maybe I'm just missing something. But every time I actually try to imagine a concrete situation in which this sort of gesture might be useful, I can't do it.

I like this! But, you know, publishing it on the internet doesn't exactly make it secret. On the other hand, keeping secrets is difficult anyway, especially in large groups.

These gestures suppose that people already know (or at least suspect) that the other one is a part of their group. So perhaps there should also be some kind of "passive" sign; one that allows you to notice that a stranger in a crowd of strangers is likely a member of your group (and then you approach them and proceed with the gesture). Something like esperantists wearing a green star.

I think this is a terrible and ridiculous idea. likely to create in-groups and out-groups and do more bad than good.

While you are willing to go down these paths have you considered sign-language representations? I am unfamiliar with them other than knowing they are there.

I like this! But, you know, publishing it on the internet doesn't exactly make it secret. On the other hand, keeping secrets is difficult anyway, especially in large groups.

These gestures suppose that people already know (or at least suspect) that the other one is a part of their group. So perhaps there should also be some kind of "passive" sign; one that allows you to notice that a stranger in a crowd of strangers is likely a member of your group (and then you approach them and proceed with the gesture). Something like esperantists wearing a green star.

Furthermore, historically, various organizations, ranging from secret societies to religions to militaries have sought to utilize very specific physical gestures as a way of communicating affiliation covertly or overtly for various purposes.

What makes you think that communicating affiliation is the primary goal of those gestures?

Outstretch right hand towards the front or other person with palm raised upwards and fingers open and slightly curled.

I would interpret that as "Give me".

I am trying, and failing, to think of any possible situation in which I would want to use one of these gestures.

If you don't know the person you're facing is another EA, the likely outcome is that you make a weird gesture and the other party is offended or confused, thinks you're creepy and weird, and avoids interacting with you in the future. Extra bonus points if they ask why you just did that weird thing, you explain it's an identity symbol for effective altruists, and now they think effective altruism is a sinister cult with weird hand gestures.

If you do know the person you're facing is another EA, why do you need a special gesture to identify you both as such?

Maybe it might be used in a situation other than one-to-one interaction like, er, that Nazi salute? But it's not like EA rallies are particularly common, and if they were you'd need this gesture to be known by everyone there, which ... doesn't seem likely to happen.

What other instances are there of this kind of gesture being used? You get them sometimes in secret societies like the Freemasons with their special handshakes, or maybe the early Christians supposedly scratching fish symbols in the dirt. But EA isn't a secret society nor (so far as I know) does it aspire to be one; effective altruists aren't persecuted and have no need to hide, and the available evidence suggests that openness about generous giving helps to encourage others to give more.

What am I missing? When would anyone use this and why? I think I need some concrete examples. The OP says things like "for various purposes" (what purposes?) and "to help us identify each other" (in what situations?) and "for the positive psychological effects" (of doing what, exactly?). I just don't get it.

For instance, with Dust Theory, you say that you gave it at most a 10% chance of being true, and it was paralyzing to you. This shouldn't be. First, you need to consider your priors and the evidence.

No, I rated the death outcome as having a 10% chance of being true. But now I rate it much lower.

How often in the past have you had the actual experience that Dust Theory suggests is possible and which you fear? What actual experiential evidence do you have to suggest that Dust Theory is true?

This:

It will be some kind of natural selection in dust world lines, which will result in more stable ones, and most likely I am already in such line. In this line dreaming is built such that it will not result in important shifts of reality. And it is true: dreaming is not unconsciousness state. I start to have dreams immediately than I fall asleep. So dreaming is built to be not interupting some level of consciousness.

Basically, the fact that we do it only a little bit accounts for our observations in ways that other cosmological theories can't.

For that matter, one of the common threads of your fears seems to be that "you" cease to exist and are replaced by a different "you" or that "you" die. But the truth is already the case that people are constantly changing. The "you" from 10 years ago will be made up of different atoms than the "you" 10 years from now by virtue of the fact that our cells are constantly dying and being replaced. The thoughts we have also change from moment to moment, and our brains adjust the strengths of the connections between neurons in order to learn, such that our past and future brains gradually diverge.

Er, you don't understand the problem. I was worried about my subjective self dying.

I think what you're doing is something that in psychology is called "Catastrophizing". In essence you're taking a mere unproven conjecture or possibility, exaggerating the negative severity of the implications, and then reacting emotionally as if this worst case scenario were true or significantly more likely than it actually is.

The proper protocol then is to re-familiarize yourself with Bayes Theorem (especially the concepts of evidence and priors), compartmentalize things according to their uncertainty, and try to step back and look at your actual beliefs and how they make you feel.

Rationality is more than just recognizing that something could be true, but also assigning appropriate degrees of belief to ideas that have a wide range of certainties and probability. What I am seeing repeatedly from your posts about the "dangers" of certain ideas, is that your assigning far too much fear to things which other people aren't.

To use an overused quote: "Fear is the mindkiller."

Try to look at the consequences of these ideas as dispassionately as possible. You cannot control everything that happens to you, but you can, to an extent, control your response to these circumstances.

For instance, with Dust Theory, you say that you gave it at most a 10% chance of being true, and it was paralyzing to you. This shouldn't be. First, you need to consider your priors and the evidence. How often in the past have you had the actual experience that Dust Theory suggests is possible and which you fear? What actual experiential evidence do you have to suggest that Dust Theory is true?

For that matter, one of the common threads of your fears seems to be that "you" cease to exist and are replaced by a different "you" or that "you" die. But the truth is already the case that people are constantly changing. The "you" from 10 years ago will be made up of different atoms than the "you" 10 years from now by virtue of the fact that our cells are constantly dying and being replaced. The thoughts we have also change from moment to moment, and our brains adjust the strengths of the connections between neurons in order to learn, such that our past and future brains gradually diverge.

The only thing that really connects our past, present, and future selves is causality, in the sense that our past selves lead to our future selves when you follow the arrow of time. Therefore, what you -think- is a big deal, really isn't.

This doesn't mean you shouldn't care about your future selves. In fact, in the same way that you should care about the experiences of all sentient beings because those experiences are real, you should care about the experiences of your future selves.

But don't worry so much about things that you cannot control, like whether or not you'll wake up tomorrow because of Dust Theory. I cannot see how worrying about this possibility will make it any more or less likely to occur. For all we know the sun could explode tomorrow. There is a non-zero possibility of that happening because we don't know everything. But the probability of that happening, given our past experience with the sun, is very very very low, and as such behaving as if it will happen is completely irrational. Act according to what is MOST likely to happen, and what is MOST likely true, given the information you have right now. Maximize the Expected Utility. Expected is the key word here. Don't make plans based on mere hopes or fears unless they are also expected. In statistics, expectation is commonly associated with the mean or average. Realistically, what will happen tomorrow will probably be a very average day.

That is being rational.

Hope that helps!