"Rationals are interested in efficient operations. If a given operation promises to be too costly for the results it gets, that is, inefficient though effective, the Rational will look for operations that are likely to take less effort to get to the same result." Rationals will listen to anybody who has something useful to offer regarding their choice of ways and means, but they will also disregard anyone who does not. Status, prestige, authority, degree, license, credential, badge of office, reputation, manners-all of these marks of social approval mean nothing to the Rationals when the issue is the utility of goal-directed action" Please Understand Me II, Page 169.
Rationals are problem solvers, knowledge seekers, efficient, independent, strong willed and they hunger for achievement. They must continue to learn all their lives, as learning is an end in itself.
Rationals haven't got time for the trivial and at times can come off as cold and aloof. They are highly efficient and resourceful and haven't got time for idle banter that does not address the issue at hand.
Everyone knows someone in their office that seems to be cold and unapproachable, but if you understand the Rationals, know this is how they operate, and you do not need to take their perceived aloofness personally.
Some better known Rationals are, Bill Gates, Abraham Lincoln, Thomas Jefferson and Walt Disney, to name a few.