More recently, rationalist has tended to have a meaning closer to its current one, but with strong negative affect associated with it. Peter Drucker, for instance, seems to use it as a term of reproach in "Adventures of a Bystander", to mean the sort of small souled narrow-minded person who thinks that they can be right and others wrong and are allowed to say so because they have reasons for their beliefs instead of having made them up to express feelings but the assumption is that one shouldn't do this because doing it leads to communism, fascism, or other forms of authoritarianism. If people don't have the right to believe what they want then some authority must have the right to tell them what to believe. Traditional conservatives can associate this attitude with communism and other badness. Basically, rationalism is used to mean affiliation with authoritarian regimes who claim the prestige of science.

@Daniel, I agree with this observation. Minimizing being wrong is a pretty recent intellectual development. Epistemic minimax is probably logically a better name, although it sort of sucks.

The James Randi definition of skeptic seems to have much overlap. I would guess that what EY is looking for has James Randi definition of skeptic as a subset of EY's rationalist belief processes.