I think rationality is useful because it is the only reliable path to truth. And truth is required to accomplishing almost everything. Except happiness...which may have been your original point.
Or more generally, inner truth. This is why I am not a rationalist or an objectivist. Human experience itself is subjective, and even if through supreme rationality we are able to pry apart our psyches and lay it bare as a pile of neurons then what? Do we feel good about that?
I choose to believe in a higher consciousness because it makes my life richer, not because I am hiding from rational, physical, objective truth.
I choose to believe in a higher consciousness because it makes my life richer, not because I am hiding from rational, physical, objective truth.