I haven't read the book yet, but each time I hear this I remember my stats teachers repeating "correlation is not causation". So, are there statistics to back this up? Example, previously high crime areas that coincided with high abortion rates in the years discussed, followed by lower crime rates today? Or is just the idea talked about? It is interesting at how quickly this thread devolved from topic discussion to the morality issue of abortion (which I'm sure there is a thread for if people want further debate).