I think of "hard" and "soft" classes as being analogous to search. Before you can search for anything, you need to be able to know what you are looking for and

I think of "hard" and "soft" classes as being analogous to search. Before you can search for anything, you need to be able to know what you are looking for and define what it means to find it. That is the sort of thing "soft" classes are about, understanding what we really want and thinking through our decisions carefully. The "hard" classes, on the other hand, basically consist of a bunch of search techniques and search optimizations for existing problem domains. So, "soft" classes teach you how to define your own problems and "hard" classes teach you how to solve existing problems.