  Cooper distinguishes natural-history based explanations from case studies. She presents them as distinct kinds of psychiatric explanation, but she doesn’t go into detail about what the other types might be, so her overall position is hard to grasp. But one idea is very clear; at least some mental illnesses are natural kinds, and natural history explanations work by “invoking natural kinds” (2007, 47). Once we know which kind an object belongs to, we can explain and predict its behaviour based on its kind membership: we can say why a substance has expanded upon being heated by invoking the fact that it’s a bit of metal, and metals expand when heated. Or we can predict that if Rex is in the kitchen then leaving the roast beef there unattended is a bad idea, since Rex is a dog and dog-meat interactions take a predictable form. And, it is hoped, we can explain why Laura hears voices by appealing to the fact that she has schizophrenia. And our confidence that she is schizophrenic warrants (pessimistic) predictions about her future.