It very well might not be but it seems to me to be so. I was thinking of it from a Misesian "human action" point of view in that we act, volitionally, towards ends. And though our subjective ends and values may or may not conform to logic and empiricism or rational standards, actions in and of themselves require rational thought to be carried out.
For example, it may be irrational for me to move to Arizona because I do not like hot weather, but for me to get from here to there requires me to act rationally (i.e. go west instead of north, choosing a mode of transportation, etc.). And thinking of the choosing to be irrational idea confused me in this light.
I may be just confusing myself for no good reason but as I pondered I figured I would throw out it there. 