Do you really want rationalists to be a group of people who aren't allowed to be optimistic?
I want rationalists to be a group of people who are as optimistic as the situation warrants.
Sure, and of course the problem in practice is figuring out what level of optimism the situation warrants. Sometimes you're not going to be optimistic enough and sometimes you're going to be too optimistic. If you're afraid of being too optimistic because you think it will make you look gullible and stupid, then you'll probably end up being too pessimistic instead, and that is also bad.
Rob Rhinehart's food replacement Soylent now has a crowdfunding campaign.
If you're interested in one or more of these benefits, send in some money! There is also a new blog post.