We need to know the ideals for which we are reaching, regardless of whether we ever actually get there. Ideals keep us focused in the right direction and provide a reference point to evaluate new things. Are we getting closer to our ideal or further from it? If you're getting further from your ideal, then you're on the wrong path.
Mokalus of Borg
PS - Without ideals, it's too easy to go off track.
PPS - Plus a lot more things look ambiguous that way.