Rationality has nothing to do with what I said. I said that groups tend to coalesce around short-term, immediate concerns. Imagination and the capacity to dream is an individual, not group, activity. It often takes a true outsider to expand the bounds of a culture's thinking or time perspective. This by definition can't come from a group.

Nor is rationality itself necessarily an ideal end goal. In fact, this obsession with rationality (exemplified by sites like Less Wrong and in general by scientism-adherents) is itself a perfect example of my point - a group of individuals stuck in their worldview, incapable of seeing beyond the walls of their own local culture.