The Natural Sciences

Samuelson attached great importance to the courses in the biological and physical sciences that he took in his sophomore year. As with his social science course the previous year, the General Introductory Course in the Biological Sciences, taught by Merle Coulter, which Samuelson described as an excel­lent survey course,¹ began with a discussion of the scientific method.

Each living unit is a pseudo-isolated system in dynamic equilibrium. Through this individual passes a steady stream of matter and energy which undergo changes in their passage. This flow of substance is con­trolled by the organization of the system so as to maintain itself as a unit despite profound replacements within it. Other systems in dynamic equilibrium show in essence all the properties of living things. It is almost impossible, for example, to distinguish a candle flame from a living organism by any definition in words. Into each come oxygen (respiration) and substances (food) which are broken down (digested), taken into the structure, and finally oxidized (metabolism), yielding energy for purposes of maintaining the organization and wastes which are removed (excreted).³

Equilibrium, a concept that Samuelson would later use to unify economics, was being applied as a general framework within which to understand the whole of the living world.

After this classification of types of life, living organisms were analyzed as “running machines,” explaining how they functioned, emphasizing bio­chemical processes. The syllabus explained that there would be no attempt “to cover comprehensively the fields of human physiology in health and dis­ease,” but a few topics would be covered “with a moderate degree of penetra- tion.”⁴ One of those topics was blood pressure, which covered the causes of hypertension, or raised blood pressure.⁵ This was of particular relevance to Samuelson because in his freshman year he had been found to suffer from hypertension and was banned from involvement in intramural sports.⁶ His father had the same problem and, though still alive, he was in poor health. Given that it was then untreatable, his father's condition will have contrib­uted to his anxiety about the problem.

Students were warned of the danger of reifying concepts, whether “mind,” “consciousness,” or the “self.” “Ideas” are not stored—they are not “immate­rial, spiritual things hiding in the subconscious” or like “old letters, waiting to be re-read.”⁷ What persists is the effects of previous sensory experiences on the nervous system. “One may as well assert,” it was claimed, “that the actual music is in a phonograph record and is released by the needle as to assume that ideas exist as entities in some hypothetical, immaterial mind or soul.”⁸ This led to a clear lesson:

The reification of abstractions has been the source of considerable confusion and error in psychological thought.

This injunction may have been in a course on biological sciences and its conclusions for the social sciences other than psychology may not have been drawn out, but it would not have been difficult for a bright student to see the implications for the study of human behavior in other contexts.

The course ended by covering genetics, eugenics, and ecology, the last of which, like the parallel course on the physical sciences, meant that it finished with geography. The section on genetics was the most mathematical part of the course, involving statistics and the curve of a normal distribution. Samuelson remembered that “His [Coulter's] discourse on simple Mendel genetics led, it appeared to a Gaussian distribution when the number of genetic attributes grew from 2, 3,.., to N = infinity.”⁹ However, the explicit mathematical content was minimal, with barely an equation to be seen in the syllabus. Samuelson later remembered this as having been his first introduc­tion to the normal distribution for which he had been prepared by attending a lecture by the sociologist William F. Ogburn, which he had attended with a girl he described simply as “a short-term date.” Forgetting to mention his assumption of a normal distribution, Ogburn had claimed that two-thirds of observations would be within x standard deviations of the mean, a claim that Samuelson believed he could disprove. He found, on his own, a copy of Fundamentals of Statistics (1925), by Louis Thurstone, a professor in the Department of Psychology, which presumably helped him think more deeply about the problem that Coulter was discussing in very simple terms. Though he had not yet seen the overall importance of mathematics, this shows that he was already following up on the mathematical elements in the lectures he was attending.

Genetics led Coulter into a discussion of eugenics, “defined roughly as human genetics.”¹⁰ Though the focus was on understanding heredity, one aim of eugenics was to control human evolution by controlling reproduc­tion. Eugenicists advocated a program involving sterilization of “hereditary defectives,” subsidies to the fit, caution in admitting “hereditarily inferior types of immigrants,” and the dissemination of information on heredity. Whatever Samuelson's reaction, it is worth noting that he was exposed to Coulter's arguments in favor of such measures, which “could surely do no harm and might do an immense amount of good.” Coulter supported his position by referring the students to Edward East's Heredity and Human Affairs (1927)—a book that he expected them to “read liberally”: the impor­tance of the topic to the modern citizen justified such a long assignment.¹¹ The assignment of this racist text shows the clear difference between what was acceptable then and what is now.

Though East recognized the great variety within racial groups, he argued that there were significant differences between races: “the negro averages about two grades lower than the English, the Scotch a fraction of a grade above, and the Athenians of the time of Pericles two grades above.”¹² Though recognizing that comparisons had to be made “with great caution,” East concluded that

One who makes a thorough study of the available evidence, however, cannot avoid concluding that the intelligence level of the negro is far below that of the white, though not significantly different from the lowest of the white subgroups. The range of averages in the white subgroups extends as far above the general average as that of the negro does below it.¹³

On average, Jews and Nordics were “great races” in that they produced more than their share of exceptional individuals. However, the price of this was a larger number of “simpletons”:

They have left their mark on every science, on every art.

Under a strict eugenic regime, where breeding was controlled, this would not be true. “Race suicide,” involving degeneration of the population, could be avoided. In this book, the conclusions of which were endorsed by his teacher as capable of doing no harm, science was being used to support a rac­ist ideology and widely held prejudices. Remarks in other parts of the course suggest that Coulter did not share East's belief that there were substantial differences between races, but he nonetheless recommended the book suf­ficiently strongly that it is hard to believe that Samuelson did not read it.

In the parallel course on the physical sciences, taught by Harvey Lemon, an experimental physicist who was soon to publish a textbook titled From Galileo to Cosmic Rays: A New Look at Physics (1934), and Hermann I. Schlesinger, an inorganic chemist who had taught at Chicago since 1907, astronomy was used as a route into physics and then into chemistry. After a lecture on the unifor­mity of nature, students were introduced to the night sky and what it meant to think of the earth as an astronomical body. Lectures in the Adler Planetarium, established only two years earlier—the first planetarium in America—served to make the material more concrete. Discussions of more abstract physics (matter and force, energy and work, the mechanics of fluids) were covered as they arose. After covering celestial bodies, from the sun to the galaxy, the course turned to the composition of matter: molecules, then atoms, electricity, magnetism, radioactivity, atomic structure, sound, and spectroscopy.

From spectroscopy it was a short step into chemical change, combus­tion, and a range of topics in chemistry that ended with the carbon cycle (providing a link with the biological sciences course).

THE STRUCTURE OF A MATHEMATICAL SCIENCE

The structure consists of definitions and axioms designed to correspond with experience, and the theorems which can be deduced from them by the laws of mathematical logic. In order for a theory to be useful in the interpretation of natural phenomena the superstructure of theorems must be in accord with experimental data as well as the axiomatic basis. The purposes of such a theory are the correlation of results which may oth­erwise seem heterogeneous and unrelated in character, and the logical prediction of results which might be difficult or impossible to discover experimentally.¹⁵

The point about mathematics being a means of bringing heterogeneous data under the same theory was then repeated specifically in relation to physics.¹⁶ The course ended by going into geology, its relation to life, meteorology, cli­mate and the weather, and mapping. In relating the distribution of mankind across the earth to geology, it was linking physics to the biological and social sciences.

Samuelson was to remember this course and Harvey Lemon more than half a century later. Though he did not say this, its message that mathemat­ics could unify seemingly different fields, and that useful theorems needed to be in accordance with data, was to find strong echoes in his economics. However, the specific point that he noted when, in 1996, he wrote to Caltech chemist Norman Davidson, with whom he had taken a calculus course at Chicago, was that it was in Lemon's course that he had first encountered the Le Chatelier Principle, an idea that was to be important in his subsequent work.^a Samuelson wrote of Lemon, “I didn't like his teleology. I preferred this [the principle of Le Chatelier] as a prosaic corollary to Jacobi's theo­rem on determinants, which is just as applicable to economics as it is to chemistry.”¹⁷ It is not clear what he meant by Lemon's “teleology,” but per­haps it was the progression from the universe to the place of mankind on the earth that Lemon might have discussed in relation to Coulter's evolutionary theories. Samuelson was correct that he had encountered the principle in Lemon's course, but his account of his response to it does not ring true; for in the same letter as the one from which the previous quotation is taken, he confessed that at that point he had not seen the importance of mathematics: “You know the brutal truth: that, late in life as an aging wunderkind, a good fairy whispered to me that math was a skeleton key to solve age old prob­lems in economics.” If he had not yet seen the significance of mathematics for his future work, and had yet to take the introductory calculus course, it is hard to believe that, for all his teachers' statements about the unifying power of mathematics, he would have seen that a principle in chemistry, that was not even described algebraically, was a more general theorem in mathematics. He simply had not studied enough mathematics to be think­ing in these terms.