So, we got into an interesting discussion the other day in a post I did on Russell Branyan. While looking at his platoon splits over the years, I noticed that when given the opportunity, he hit left-handed pitching rather well despite a reputation to the contrary. Here’s how Branyan did when he was allowed to face lefties:

Compare this with how he fared when he wasn’t given the chance to face lefties:

The guy hit .264/.333/.604 against southpaws in 162 plate appearances from 2001 to 2003. How was he rewarded? By seeing his playing time against that subset of pitchers reduced. Gee, there’s a sensible response.

Now, I don’t want to fixate on Branyan too much because there’s a larger question looming in my mind. It has to do with matters of perception and reality.

Uh-oh, he’s going to start quoting Castaneda; lay off the peyote, dude.

My question is this: Why is it that, when presented with evidence that doesn’t fit their preconceptions, some people will continue to behave as though those preconceptions represent what is actually happening in the world?

It’s a little unsettling if you think about it… which is why I recommend you don’t.