Robert E. Lucas Jr. discusses the evolution of macroeconomics and its role in preventing economic depressions. He argues that macroeconomics has largely succeeded in this goal, with long-term supply-side policies offering greater welfare gains than short-term demand management. Lucas outlines a framework for evaluating public policies based on individual preferences and welfare gains. He uses examples to show that changes in monetary and fiscal policies can significantly increase consumption levels. Lucas also explores the potential gains from improved stabilization policies, noting that eliminating consumption variability could lead to a small welfare gain, around 0.05% of consumption. He reviews studies on the sources of business cycle variability, finding that nominal shocks account for a small portion of output fluctuations. Lucas also addresses risk aversion, noting that high risk aversion is necessary to explain the equity premium puzzle. He concludes that the potential gains from further reductions in business-cycle risk are small, around 0.1% of consumption. Lucas emphasizes the importance of considering distributional effects and the role of incomplete markets in shaping welfare gains. He also discusses the potential for policies that reduce risk variability to improve welfare, and concludes that while stabilization policies may offer modest gains, they are not as significant as supply-side reforms. The lecture highlights the importance of understanding the relationship between macroeconomic policies and welfare outcomes, and the need for further research in this area.Robert E. Lucas Jr. discusses the evolution of macroeconomics and its role in preventing economic depressions. He argues that macroeconomics has largely succeeded in this goal, with long-term supply-side policies offering greater welfare gains than short-term demand management. Lucas outlines a framework for evaluating public policies based on individual preferences and welfare gains. He uses examples to show that changes in monetary and fiscal policies can significantly increase consumption levels. Lucas also explores the potential gains from improved stabilization policies, noting that eliminating consumption variability could lead to a small welfare gain, around 0.05% of consumption. He reviews studies on the sources of business cycle variability, finding that nominal shocks account for a small portion of output fluctuations. Lucas also addresses risk aversion, noting that high risk aversion is necessary to explain the equity premium puzzle. He concludes that the potential gains from further reductions in business-cycle risk are small, around 0.1% of consumption. Lucas emphasizes the importance of considering distributional effects and the role of incomplete markets in shaping welfare gains. He also discusses the potential for policies that reduce risk variability to improve welfare, and concludes that while stabilization policies may offer modest gains, they are not as significant as supply-side reforms. The lecture highlights the importance of understanding the relationship between macroeconomic policies and welfare outcomes, and the need for further research in this area.