Nobody wants to hurt themselves

And nobody hurts themselves in order to get attention. This is a topic where it's easy to violate the Don't Say Rule.

As weird as it may sound to your ears, all behaviors, including self-injurious behaviors, happen because they've been reinforced. In the complexities of real life, we're swimming in an ocean of simultaneously intertwining behavioral contingencies that are constantly interacting in such ways that the effects on our behavior can be unpredictable and surprising. That's why we begin the course, and end up spending most of it, on the basic principles of behavior, which we learn by studying pretty simple examples. You're already realizing that mastering even those basic principles is quite a challenge.

Chapter 19 is about concurrent contingencies, and there we'll be looking specifically at how simultaneous behavioral contingencies interact to control behavior. You could make an argument that it's the most important chapter in the book because it formally introduces the reality of that ocean of intertwining contingencies that I referred to, which is the real world.