摘要：In this Article, I focus on the economics of financial markets and regulation rather than the broader philosophical inquiry of a companion article, and I narrow the competing positions to libertarianism and liberalism. I take more of an historical approach, following the development of Austrian and Keynesian theories of the business cycle from their origins in the 1930s to today. I consider the details of recent financial regulation less than in the companion article, but I consider financial regulation in tandem with monetary and fiscal policy more than in that article. Considering financial regulation along with monetary and fiscal policy is a worthwhile move. Each of these three types of interventions can help both to dampen inflationary booms and also to shorten and ease recessionary busts. Thus, to some extent, the three types of policies are substitutes. The optimal level for each depends in part upon what is happening with the other two. Part II of this Article categorizes approaches to governmental interventions to stabilize the markets into four types. The categorization is based on two distinctions. One distinction is between libertarians, who greatly distrust government and advocate at most very limited interventions, and liberals, who distrust the volatility of financial markets and advocate more extensive interventions. The other distinction focuses on the source of distrust of markets or governments. Distrust may emphasize problems of greed or of ignorance. As I note, a distinctive and welcome characteristic of the Austrian and Keynesian theories is that they focus more on ignorance than on greed. Part III begins the analysis of Austrian and Keynesian theories of the business cycle, describing some important similarities as well as differences. Each focuses on the importance of investor expectations in making investment decisions in the face of deep uncertainty. Both see investors regularly becoming involved in speculative booms in which optimistic expectations of future profits lead to overly high levels of capital investment. But the theories differ in their analysis of the source of these expectations. Austrians blame central bank monetary policy, while Keynesians see them as the result of high animal spirits following a period of relative calm and prosperity. Both theories agree that after a while such booms become unsustainable. Eventually expectations shift, and a contraction begins. The contraction can be long and painful, especially as banks, businesses, and households must unwind the large amounts of debt incurred during the boom. The two theories
