My confusion isn't coming from the term selfish, but from the term unselfish agent. You clearly suggested that such a thing exists in the quoted statement, and I have no idea what this creature is.

I wrote, "Even if you don't agree that rational agents are selfish, your unselfish agents will be out-competed by selfish agents." The "unselfish agent" is a hypothetical that I don't believe in, but that the imaginary person I'm arguing with believes in; and I'm saying, "Even if there were such an agent, it wouldn't be competitive."

My argument was not very clear. I wouldn't worry too much over that point.

You just said the opposite of what you said in your original post here, that the LHC was turned on for no practical advantage.

No; I said, "no practical advantage that I've heard of yet." First, the word "practical" means "put into practice", so that learning more theory doesn't count as practical. Second, "that I've heard of yet" was a qualifier because I suppose that some practical advantage might result from the LHC, but we might not know yet what that will be.