"The reader may benefit from my explanation of the key turning points in my own thinking, during the six years of research. Ever since my graduate studies at Yale, the quest for a better understanding of the process of economic growth has been an important part of my research. Much of the work on economic growth in the post war period was conducted under the assumption of perfect competition. Paul Romer was among those who demonstrated that one cannot study economic growth and technological innovations within the framework of a competitive model of an economy. This observation led him to concentrate on the effects of R&D and intentional inventions on the rate of growth, but my conclusion was different. It led me to the first, central, theme of this book: it follows from the observation that once technological inventions are introduced, firms with different technological knowledge have different market positions and the vision of small, equal opportunity, firms is not applicable"--