Chose your battles

What is really worth fighting for?  Is it your pride, your reputation, your ability to say "I told you so"?  I wonder if there isn't a gene in all of us that thinks we have a right to be right and we fight for it.  I know I personally get very passionate when I believe I am right and have a hard time letting go until I have convinced others that I am right.  I work hard and feel my blood pressure rise each time I am "challenged" about something.  But really is it worth it?  In the long run is there a win for anyone when you have to fight to prove you are right?