The Future of Life Institute (FLI) published an open letter against reckless nuclear escalation and use. It only took me about 1 min to read it and add my signature. I believe it was the most cost-effective action of my week, and I encourage EA Forum readers to sign it too!

I guess signing the letter leads to a reduction in existential risk of the order of magnitude of 10^-13 (=10^-(3 + 6 + 4)), assuming:

- The existential risk due to nuclear war from 2021 to 2120 is 0.1 %
^{[1]}, as guessed by Toby Ord in Table 6.1 of The Precipice. - The existential risk reduction caused by FLI's open letter is 10^-6 of the above if 10 k people sign the letter.

10^-13 might seem small, but it is of the same order of magnitude of the annual existential risk footprint of the mean human, which I estimated here to be 2*10^-13. The concept of personal footprint is flawed in many important ways, and my calculations are quite speculative. That being said, I still think they point to the high cost-effectiveness of signing the letter. For example, I would be very happy to cancel my carbon footprint for a cost of 1 min!

^{^}I have also estimated the probabilility of extinction due to nuclear in the 21st century to be 0.3 %.

I'm not sure why you think 10k people signing it matters (as opposed to which people), or why you assume the factor is 10^(-6). I read this post and I'm not sure the estimate is anywhere close. By that I mean that it could be tens of orders of magnitude off, or even that the sign of the estimate could be wrong and it would be bad for this to get many signatures.

I think it probably would have been more useful to people if you'd discussed more generally why you think this letter might have a good effect rather than trying to quantify existential risk reductions from individual EA forum users' signatures (which I take to be extremely intractable).

Hi Thomas,

Thanks for sharing your thoughts!

I think the number of people signing matters because, holding the mean influence per person constant, the more people sign, the greater the influence of the letter. Of course, who signs is also important! 10^-6 is just my direct intuitive guess.

The expected effect has an upper limit of 1, so 10^-13 cannot be an underestimate by tens of orders of magnitude (at most, it can be an underestimate by 13 orders of magnitude). However, it can theoretically be an overestimate by tens of orders of magnitude if it is smaller than 10^-33 (= 10^-(13 + 20)). The mean effect being this low (or negative) would imply FLI's efforts on this letter to be useless (or harmful) in expectation. I expect FLI's efforts to be useful in expectation, so I guess signing the letter is also useful.

Moreover, for the reasons Brian Tomasik presented here, I do not think the expected effects of signing can reasonably differ tens of orders of magnitude.

Fair point. I signed the letter 2 days ago without doing any explicit calculations at all. My calculations are just for illustration, but if it is worth doing, it is worth doing with made-up statistics (which mine obviously are; please do not take them too seriously!).