“I believe SIAI’s probability of success is lower than what we can reasonably conceptualize; this does not rule it out as a good investment (since the hoped-for benefit is so large), but neither does the math support it as an investment (donating simply because the hoped-for benefit multiplied by the smallest conceivable probability is large would, in my view, be a form of falling prey to “Pascal’s Mugging”.”
“I believe SIAI’s probability of success is lower than what we can reasonably conceptualize; this does not rule it out as a good investment (since the hoped-for benefit is so large), but neither does the math support it as an investment (donating simply because the hoped-for benefit multiplied by the smallest conceivable probability is large would, in my view, be a form of falling prey to “Pascal’s Mugging”.”
http://blog.givewell.org/2009/04/20/the-most-important-problem-may-not-be-the-best-charitable-cause/