Much of Fogel's late writing incorporated the concept of technophysio evolution, a process that he described as "the synergism between rapid technological change and the improvement in human physiology." By using height as a proxy for health and general well-being, Fogel observed dramatic improvements in health, body size, and mortality over the past 200 years. This phenomenon is examined more fully in The Escape from Hunger and Premature Death, 1700–2100: Europe, America, and the Third World and The Changing Body: Health, Nutrition, and Human Development in the Western World since 1700 (both published by Cambridge University Press).
Fogel was born in New York City, the son of Ukrainian Jewish immigrants from Odessa (1922). His brother, six years his senior, was his main intellectual influence in his youth as he listened to him and his college friends intensely discuss social and economic issues of the Great Depression. He graduated from the Stuyvesant High School in 1944. Upon his graduation he found himself with a love for literature and history and aspired for a career in science, but due to an extreme pessimism about the economy in the second half of the 40s, he shifted his interest towards economics. He was educated at Cornell University, where he majored in history with an economics minor, and became President of the campus branch of American Youth for Democracy, a communist organization. After graduation in 1948, he became a professional organizer for the Communist Party. After working eight years as a professional organizer, he rejected communism as unscientific and attended Columbia University, where he studied under George Stigler and obtained an MA in economics in 1960. He received a PhD from Johns Hopkins University in 1963.
The work of Fogel was largely influenced by the McKeown thesis. Since 1955, the British public health scientist Thomas McKeown had developed a theory that the growth of population since the 18th century can be attributed to a decline in mortality from infectious diseases, largely to a better standard of living, particularly to better nutrition, but later also to better hygiene, and only marginally and late to Medicine. The work of Fogel and collaborators provided the necessary evidence that more and better food was the main drive for the reduction in mortality from infectious diseases. As summarized by Noble laureate Angus Deaton (2013, pp 91–92):
He began his research career as an assistant professor at the University of Rochester in 1960. In 1964 he moved to the University of Chicago as an associate professor. From 1968 to 1975 he was also a visiting professor at Rochester in autumn semesters. During this time he completed some of his most important works, including Time on the Cross (in collaboration with Stanley Engerman). He also mentored a large group of students and researchers in economic history, including his colleague Deirdre McCloskey at Chicago. In 1975 he left for Harvard University, and from 1978 on he worked as a research associate under the National Bureau of Economic Research in Cambridge, Massachusetts. In 1981 he returned to the University of Chicago, where he directed the newly created Center for Population Economics at the Booth School of Business.
Fogel's first major study involving cliometrics was Railroads and American Economic Growth: Essays in Econometric History (1964). This tract sought to quantify the railroads' contribution to U.S. economic growth in the 19th century. Its argument and method were each rebuttals to a long line of non-numeric historical arguments that had ascribed much to expansionary effect to railroads without rigorous reference to economic data. Fogel argued against these previous historical arguments to show that onset of the railroad was not indispensable to the American economy. Examining the transportation of agricultural goods, Fogel compared the 1890 economy to a hypothetical 1890 economy in which transportation infrastructure was limited to wagons, canals, and natural waterways. Fogel pointed out that the absence of railroads would have substantially increased transportation costs from farms to primary markets, particularly in the Midwest, and changed the geographic location of agricultural production. Despite this consideration, the overall increase in transportation costs, i.e., the "social savings" attributable to railroads, was small – about 2.7% of 1890 GNP. The potential for substitute technologies, such as a more extensive canal system or improved roads, would have further lowered the importance of railroads. The conclusion that railroads were not indispensable to economic development made a controversial name for cliometrics.
Fogel's most famous and controversial work is Time on the Cross (1974), a two-volume quantitative study of American slavery, co-written with Stanley Engerman. In the book, Fogel and Engerman argued that the system of slavery was profitable for slave owners because they organized plantation production "rationally" to maximize their profits. Due to economies of scale, (the so-called "gang system" of labor on cotton plantations), they argued, Southern slave farms were more productive, per unit of labor, than northern farms. The implications of this, Engerman and Fogel contended, is that slavery in the American South was not quickly going away on its own (as it had in some historical instances such as ancient Rome) because, despite its exploitative nature, slavery was immensely profitable and productive for slave owners. This contradicted the argument of earlier Southern historians.
In 1989 Fogel published Without Consent or Contract The Rise and Fall of American Slavery as a response to criticism stemming from what some perceived as the cold and calculating conclusions found in his earlier work, Time on the Cross. In it he very clearly spells out a moral indictment of slavery when he references things such as the high infant mortality rate from overworked pregnant women, and the cruel slave hierarchies established by their masters. He does not write so much on what he had already established in his previous work, and instead focuses on how such an economically efficient system was threatened and ultimately abolished. Using the same measurement techniques he used in his previous work, he analyzed a mountain of evidence pertaining to the lives of slaves, but he focuses much more on the social aspects versus economics this time. He both illustrates how incredibly hard and life-threatening the work of a slave was, as well as how they were able to form their own culture as a resistance to slavery. His main point ultimately comes across, though, as he explains how a small group of very vocal and committed religious reformers led the fight against slavery until it became a political force that captured the attention of the President of the United States. His book delves deeply into why some of America's most widely respected Leaders went from seeing slavery as a highly profitable workforce (which his findings indicate as true) to something that must be abolished on moral grounds.
In 1993, Robert Fogel received, jointly with fellow economic Historian Douglass C. North, the Nobel Memorial Prize in Economic Sciences "for having renewed research in economic history by applying economic theory and quantitative methods in order to explain economic and institutional change". In his Nobel lecture, titled "Economic growth, population theory, and physiology: the bearing of long-term processes on the making of economic policy", he emphasises his work done on the question of nutrition and economic growth. Fogel joins a growing list of Nobel prize winners affiliated with the University of Rochester.
In 2000 Fogel published The Fourth Great Awakening and the Future of Egalitarianism in which he argued that America has been moving cyclically toward greater equality, largely because of the influence of religion, especially evangelicalism. Building on his work on the demise of slavery, he proposed that since evangelicalism was largely responsible for ending the institution he found to be economically profitable, that religion would continue to fuel America's moral development. Fogel diagrammed four "Great Awakenings", called (by others) "The Fogel Paradigm." "Fogel’s paradigm is drawn from what he believes are cycles of ethical challenges America has undergone provoked by technological innovations that create moral crises that, in turn, are resolved by evangelical awakenings."
A portion of Time on the Cross focused on how slave owners treated their slaves. Engerman and Fogel argued that because slave owners approached slave production as a Business enterprise, there were some limits on the amount of exploitation and oppression they inflicted on the slaves. According to Engerman and Fogel, slaves in the American South lived better than did many industrial workers in the North. Fogel based this analysis largely on plantation records and claimed that slaves worked less, were better fed and whipped only occasionally – although the authors were careful to state explicitly that slaves were still exploited in ways which were not captured by measures available from records. This portion of Time on the Cross created a firestorm of controversy, although it was not directly related to the central argument of the book – that Southern slave plantations were profitable for the slave owners and would not have disappeared in the absence of the Civil War. Some criticisms mistakenly considered Fogel an apologist for slavery. In fact, Fogel objected to slavery on moral grounds; he thought that on purely economic grounds, slavery was not unprofitable or inefficient as previous historians such as Ulrich B. Phillips had argued.
Fogel researched and wrote on numerous fields in his career, including not only economic history but also demographics, physiology, sociology of the family, nutrition, China's economic development, philosophy of science, and other related fields. He integrated insights from such diverse fields in his attempts to explain important historical phenomena such as the dramatic fall in mortality rates from the 18th to the 20th century. His former colleague Deirdre McCloskey credits Fogel with "reuniting economics and history". He advised many students who went on to become prominent economic historians, so that many economic historians in the United States trace their academic lineage to him.