Can classical economics help figure out climate change and support policies that slow global warming? Yale Sterling Professor of Economics William Nordhaus thinks so. In his new book, The Spirit of Green: The Economics of Collisions and Contagions in a Crowded World (Princeton UP, 2021), Nordhaus tackles the "externality" that is pollution and carbon emissions. By making several adjustments to how we treat this externality in economic terms, it can be brought back into the "system" whereby sensible regulation, market relations, and innovation can lead to markedly lower levels of pollution and greenhouse gas emissions. The most important of those adjustments is getting the price of carbon right. In many parts of the world, there is no formal price of carbon. Setting it at $40 per ton (or higher) will not be easy, not least because competing nation-states will need to agree to and abide by a universal carbon tax.   Despite these challenges, Nordhaus ends on an optimistic note. We have the means, we have the technology.... And as an example, he points to how a Covid vaccine was developed in record time after adjustments to the system of incentives and regulations. Daniel Peris is Senior Vice President at Federated Hermes in Pittsburgh. He can be reached at DanielxPeris@gmail.com or via Twitter @HistoryInvestor. His History and Investing blog and Keep Calm & Carry On Investing podcast are at https://strategicdividendinves...