“Pascal’s wager is a famous argument for why one should believe in God. If God exists, then eternal life in heaven or hell is at stake, but if God doesn’t exist, one’s belief does not matter much – so one should wager on the former. (The validity of this argument has been discussed at length.)
More generally, whenever we consider two hypotheses H1 and H2 about the world, the stakes may be higher in one of the two cases – say, if H1 is true. This is a reason to act as if H1 is true, even if it is not most likely. For instance, the precautionary principle emphasises caution towards potentially harmful innovations (e.g. a new medicine) as long as we have substantial uncertainty.
In this post, I will consider wagers that are relevant to effective altruism – that is, hypotheses that would allow us to have a particularly large impact. I’m most interested in reducing future suffering, but many of these wagers also apply to other goals.”