Why Run?

I had an interesting discussion yesterday with an old and fascinating friend about why people run. Some may say, if it hurts, as long distance runners often complain it does, why continue? Why put your self through that? Good questions, especially from non runners who have not experienced the freedom running brings, the tranquility of being the only one on a road or trail early in the morning. But there are other reasons. I run to be fit, to challenge myself - mind and body, to see what limits I can overcome - mainly my own self doubt, to be an active role model for my children, to meet like minded people. Very simply, I RUN BECAUSE I CAN, and in that simplicity is the joy, the self transformation, the awareness of my strengths and weaknesses. And pain can put you in the moment like nothing else. My question is, if I can, why wouldn't I run?