Abstract
Baseball rules prohibit pitchers from intentionally throwing at batters. When a pitcher does so, however, it is common practice for a pitcher on the opposing team to retaliate by throwing at the first player of the offending team to bat the next inning, and for umpires to ignore the rule forbidding that. I argue that player retaliation in the form of one for one is a better response to the initial violation than any other that is available, one for one can be justified as payback and for anticipated good consequences, and everyone who becomes a professional baseball player has consented to the practice. From these claims, I conclude that one for one is in the best interest of baseball, it is best if umpires follow common practice and wink at the rule forbidding it, and players cannot complain if they are told to throw at batters in certain circumstances, or are thrown at in just those circumstances