"One seeking to understand the recurrent ebb and flow of economic activity characteristic of the present day finds these numerous explanations both suggestive and perplexing. All are plausible, but which is valid? None necessarily excludes all the others, but which is the most important? Each may account for certain phenomena ; does any one account for all the phenomena ? Or can these rival explanations be combined in such a fashion as to make a consistent theory which is wholly adequate?"

“In physical science and in industrial technique... we have emancipated ourselves... from the savage dependence upon catastrophes for progress... In science and in industry we are radicals—radicals relying on a tested method. But in matters of social organization we retain a large part of the conservatism characteristic of the savage mind...”

“I began studying philosophy and economics about the same time. The similarity of the two disciplines struck me at once. I found no difficulty in grasping the differences between the great philosophical systems as they were presented by our textbooks and our teachers. Economic theory was easier still. Indeed, I thought the successive systems of economics were rather crude affairs compared with the subtleties of the metaphysicians. Having run the gamut from Plato to T. H. Green I felt the gamut from Quesnay to Marshall was a minor theme. The technical part of the theory was easy. Give me premises and I could spin speculations by the yard. Also I knew that my 'deductions' were futile...”

“This book offers an analytic description of the complicated processes by which seasons of business prosperity, crisis, depression, and revival come about in the modern world. The materials used consist chiefly of market reports and statistics concerning the business cycles which have run their course since 1890 in the United States, England, Germany and France.”