The "When I'm 70" Rule

I've been trying to implement a new perspective in my doings.  It is inevitable that you get into conflict over things at home, at work, at church.  So I'm trying to ask myself, "Will I look back at this particular conflict when I'm 70 and think I made a big fuss over nothing?  Will I even feel foolish for getting so worked up?"  If so, then yield to the other person.  It's not worth it.

This is along the lines of, "Don't sweat the small stuff. P.S. Everything is small stuff."