"The idea of writing this book was dismissed as crazy by many of my friends. The book is here, now, but they may still be right, given the breadth and complexity of our field of enquiry: contemporary economic research, from the Second World War to the present. Consider the mass of economic journals (some thousands) and books (ditto) published yearly; consider the fact that economists active in the period under consideration by far outnumber the authors of economic writings of all the previous periods. Thus, although there are on average a thousand pages read behind every single page of this book, my ignorance remains pervasive and the account of each area of research will be scanty and simplified"--