While writing this book, I have had in mind two sets of readers: first, undergraduate and graduate students who may be looking for alternative approaches to thinking about theoretical, applied and policy issues in economics. By presenting a structure of the thought (and its origins) that I have found so helpful over my working life I hope to at least interest and possibly even enthuse this first set. Secondly, I also hope that what I have written may interest teachers and researchers in economics, not so much perhaps for the details of the analysis, with which many will be familiar, but for the way in which one person at least sees the interconnections and interrelationships which have emerged as our discipline has evolved and developed.

The ideas in the book themselves have evolved and developed for me over the past fifty years, in both lectures and research. My model is not exactly Dennis Robertson's three volumes of lectures on Economic Principles in Cambridge, Robertson (1957, 1958, 1959); but I suppose it has something in common with them, even with his admission that ‘if it is all wrong, it can't be helped now’ (Robertson 1957, 7). I trust, though, that I have not written in quite as querulous a tone as that into which Robertson sometimes lapsed, for I remain, as ever, a happy and enthusiastic, even optimistic, person who nevertheless is willing to admit that he may be wrong.