It is possible to draw some limited conclusions from the examples of economics in action discussed in Part I. It would be wrong either to dismiss economics altogether (the discipline clearly has some successes to its credit) or to sweep such concerns aside (there are reasons to believe it may have played a significant role in some major disasters). It also seems clear that economics is most successful where problems are narrowly defined and that its application is most problematic when wider issues, involving politics or social phenomena, need to be considered. Neither of these conclusions should be at all surprising, though it is surprising how often commentators focus on one and ignore the other.

To understand what is going on in economics – to see the bigger picture behind these case studies – it is necessary to delve a little deeper, for understanding this bigger picture involves trying to understand why economists think as they do. It is otherwise impossible to understand the disagreements that persist in the subject. To do this, we need to look into its recent history. A good place to start is with economists' definitions of economics. Although such definitions may not describe what economists actually do, they reveal much about the way they understand what they are doing. Chapter 6 explores this through discussing the question of what it means to be scientific, for this perspective reveals economists' views on what constitutes a good argument within their discipline.