As you have read through this book, you will probably have noticed that different social psychologists have very different ideas about what is important about how human beings act with one another. Partly, these different ideas come about because anyone doing psychological research needs to focus on a particular topic or area — human beings are just too complicated to be able to look at everything at once. Partly, they come about because the psychologists concerned are working within different traditions of social psychology. And partly, too, it happens because people are working at different levels of explanation — they are analysing one level of behaviour, and possibly incorporating one or two others, but not the whole spectrum.