The previous lecture ended with a glimpse of the 20th century as it evolved in America. Although the number of scientists increased in the USA after the Civil War - membership of the American Association for the Advancement of Science (AAAS) went from 536 in 1870 to 1,555 in 1880 and to 1,925 in 1900 (Cohen, 1965) - their contributions to society were less in the area of general science than in technical innovation. When we now return to 19th century Europe we find such rapid development in fundamental areas of science that it becomes impossible to do justice to every scientist that contributed to the growth of scientific knowledge, and we have to be content with a rather elementary summary.
The 19th century was truly the century of science. Science affected all areas of life. Scientific inventions changed people's lifestyle, whether it was public transport, street lighting, balloon and aircraft flight, radio or other new means of communication. The names of many 19th century scientists are remembered as units for physical properties of nature:
|scientist||lived||in||now unit of|
|C.-A. de Coulomb||1736 - 1806||France||electrical charge|
|A.-M. Ampère||1775 - 1836||France||electrical current|
|C. F. Gauss||1777 - 1855||Germany||magnetic induction|
|H. C. Ørsted||1777 - 1851||Denmark||magnetic field strength|
|G. S. Ohm||1789 - 1854||Germany||electrical resistance|
|M. Faraday||1791 - 1867||England||electrical capacitance|
|W. Thomson (Lord Kelvin)||1824 - 1907||England||absolute temperature|
|H. Hertz||1857 - 1894||Germany||wave frequency|
These names indicate important developments in the area of physics. If we also remember the parallel developments in chemistry (Lecture 24) and biology (Lecture 25) there can be no doubt that the 19th century witnessed more new scientific insight than any period before.
The period from the years before the American Revolution to the middle of the 19th century (1760 - 1840) has become known as the Industrial Revolution. It began in England, where it initiated far-reaching changes in the structure of its society. Scientific analysis of the laws of society and its economy was therefore another important development of the period.
The beginning of the Industrial Revolution is often identified with James Watt's introduction of an efficient steam engine in 1765. While it is true that the steam engine played an important part in the development of factories, it was not the most important ingredient. The factors that characterized the Industrial Revolution are usually given as
It is evident from the list of changes that they describe the transition from an agrarian-based to a factory-based urban society, in other words the transition from feudalism to capitalism: The Industrial Revolution brought the changes in production, the bourgeois revolution brought the corresponding political change. The most significant development in the area of production was without doubt the invention of machines. Energy sources had been available before, and water and wind mills had undergone much development since the Middle Ages. The steam engine made the location of production centres independent of rivers and provided more continuous power than wind. It was not responsible for the unimaginable misery and starvation that accompanied the Industrial Revolution. (In 1850 almost half of all English children died before reaching their fifth birthday; Crowther, 1967) On the contrary, the steam engine alone would have created a demand for labour in locations that previously lacked a suitable power source. It was the invention of the mechanical machines such as the "Spinning Jenny" of 1768 and the power loom of 1784 that created mass unemployment and turned productive people into begging vagrants. The Spinning Jenny did not depend on steam power; it was powered manually by turning a wheel.
The new mechanical inventions arose from the old tradition of the technical trades. Science did not contribute much to them. Scientific mechanics had culminated in Newton's Laws, which related to the universe rather than the factory floor. The laws had been formulated in the 17th century. By the end of the 18th century England had embarked on industrialization; in the area of classical mechanics it had become more a user of scientific insight than a producer. This role had fallen to French scientists and the scientific institutions established by the French Revolution. They completed Newton's work and in the process laid the seeds for the theory of relativity.
Newton's Laws were formulated for what is now called an "absolute coordinate system." Such a system of coordinates is either at rest, or it moves in a straight line at constant speed. As Galilei had already pointed out, whether a system is at rest or moves at constant speed is impossible to determine. But the Earth revolves around its axis, and a point on the Earth's surface is neither at rest, nor does it move at constant speed on a straight line. Applying Newton's laws to movement on a rotating Earth required an additional step before the Newtonian or "classical" mechanics could be considered complete.
The theoretical closure of the problem was achieved by the French engineer Gustave-Gaspard Coriolis, who had started his career with a work on the efficient use of machines. Through mathematical analysis he showed in 1835 that Newton's Laws can be applied to a rotating coordinate system if an "apparent" or "virtual" force is added to the balance of acting forces. This force, which soon became known as the Coriolis force, produces an apparent deflection of moving bodies from a straight path. It is largest at the two poles and disappears at the equator. In 1851 the physicist Jean-Bernard-Léon Foucault used Coriolis' theory to demonstrate that the Earth does indeed revolve around its axis. His "Foucault pendulum" has become a popular demonstration experiment in science museums around the world.
While Coriolis and Foucault brought classical mechanics to satisfactory closure, they could not improve the situation in optics. Newton had performed optical experiments and described light as a stream of particles. His contemporary Christiaan Huygens had described light as waves. Huygens' work was more or less ignored until the beginning of the 19th century, when Fizeau, Foucault and others became keenly interested in the speed of light, and various experiments in optics supported Huygens' analysis. This created a conundrum; in the words of Foucault:
The "duality" of light - particle stream versus continuous wave - still exists today and will require further discussion in Lecture 28. The 19th century contributed much to its understanding. It required a change of emphasis from the study of forces to the study of fields. This process was greatly assisted by the rapid industrialization in England, which fostered an increasingly close association between science and technology.
The first machines of the Industrial Revolution were mechanical devices driven by the power of steam. This promoted the study of the thermodynamics of gases, which in turn led to technical innovation; Watt's improved steam engine was a direct result of research performed at the universities of London and Glasgow (Lecture 21). The discovery of the laws of electricity and magnetism proved even more promising for industrial applications, and the demand for scientific research could no longer be satisfied without significant financial support. This led to rapid growth of universities and technical colleges and to the final replacement of the wealthy individual, who could afford to dedicate his (and occasionally her) life to science, by the career researcher at a university.
But the study of electricity provided some surprises. Guided by the ideas of the philosopher Immanuel Kant, Hans-Christian Ørsted showed in 1820 that the passage of an electrical current through a wire affected a nearby magnetic needle. If this was to be interpreted in terms of Newtonian mechanics this could only mean that electricity consisted of matter that could exert a force on the matter in the needle.
That the law of attraction between electric charges had the same form as Newton's Law of Gravity had already been established at the end of the 18th century by Charles-Augustin de Coulomb, one of the last wealthy individuals who had turned to science. In 1839 Carl Friedrich Gauss had developed the theory of electrical potential in analogy to the gravitational potential. This supported the idea of electricity as a force attached to a body. But Ørsted's experiment connected electricity with magnetism; the needle did not carry an electrical charge, and a balance of forces between the current in the wire and the movement of the needle required the transformation of an electrical into a magnetic force or vice versa. It was only logical that Ørsted saw chemical affinity, electricity, heat, magnetism, and light all as different manifestations of the basic forces of attraction and repulsion.
In 1831 Michael Faraday discovered induction. He would spend the rest of his life trying to convert various forces into each other. But he concentrated on the patterns of forces produced by electric currents and magnets, and his many experiments laid the foundations for a new concept of physics called field theory, in which the energy of a system is assumed to be distributed in space and not localized in particles.
The idea that forces do not have to be attached to particles had already been formulated in the 18th century by Immanuel Kant, whose training in physics influenced his philosophy greatly. As a philosopher Kant approached the problem from the question of perceptibility of the world and said that the human mind cannot perceive matter in its absolute form; all the human mind can know is forces. In his view forces do not require particles for their existence, they can also occupy the space between particles; it was even conceivable that the particles could be eliminated entirely, so that only space containing forces remained. Such considerations were at odds with the Newtonian physics of Kant's lifetime but were revived as a representation of reality in the new field theory of the 19th century. They also suited the general spirit of the late 18th and first half of the 19th century known as Romanticism that had replaced the spirit of Enlightenment. Romanticism found its most prominent expression in music and literature, where it emphasized the subjective and mystical and preferred the senses over the intellect and emotion over reason. But the scientific concept that a network of forces exists in space that ties the cosmos together into a unified system, that all forces are related to each other and that the whole is more than the sum of its parts, had a definite Romantic sound to it and found particularly easy acceptance in the prevailing intellectual environment.
By the middle of the 19th century the contest between particles and waves had been won by the waves. Mathematics played a large part in the outcome; some of the greatest advances in mathematics were made during this period. Gauss had led the way. Siméon-Denis Poisson had worked out the differential equation that controls force fields. William Thomson (Lord Kelvin) had shown that such disparate phenomena as electricity, magnetism, thermodynamics, hydrodynamics, mechanics and heat could all be described through equations that transformed one form of energy into all others. James Clerk Maxwell collected the findings of Gauss, André-Marie Ampère and others into a set of equations that were satisfied by wave solutions. Light thus became a special form of electromagnetic wave.
Today Maxwell's equations form the basis for all data collection and observations from satellites; they have proven their value over and over again. In the 19th century they appeared to have discredited the corpuscular theory of light once and for all. The world of particles was left to the chemists, who developed the idea of atoms of different atomic weight. (Lecture 24) But the 19th century knew only approximate solutions to the equations. When the complete solution was derived in the 20th century it required a return to particle physics. (Lecture 28)
To conclude this brief discussion of the beginnings of wave theory we have to mention a diversion that caused many scientists to spend much of their time on a fruitless exercise. Before the 19th century wave propagation had always been linked to a medium. Ocean waves propagate on water, sound waves propagate through air. It thus appeared logical that light waves and electromagnetic waves required a propagation medium as well. Physicists therefore postulated the existence of an "ether" that filled the universe and allowed the light to reach the Earth from its stars, and Maxwell, arguing that "it would be bad philosophy to people space with new media every time a new phenomenon had to be explained," (Tonnelat, 1965) assumed that the same ether allowed the propagation of electromagnetic waves. Experiments to prove the existence of an ether were undertaken by many scientists and continued well into the 1930s. All ended with negative results.
Progress in the understanding of the laws of nature during the 19th century was not restricted to the natural sciences. The evolution of the capitalist society led to increased understanding of the laws that govern human societies as well. This development occurred mainly in England, the leading industrialized nation of the time, where the main traits of modern society were evolving soon after the beginning of the century.
First reactions to the widespread misery - documented by the industrialist Friedrich Engels in his scientific study Die Lage der arbeitenden Klasse in England (1845; "The Condition of the Working Class in England in 1844") - went in two directions. When the introduction of factories destroyed the cottage industry the Luddite movement reacted to the disastrous deterioration of the living conditions of the working class by destroying factories and machinery. The movement reached its greatest strength in 1811 - 1813 but was soon violently suppressed.
Ten years later the utopian socialist movement of the Welsh industrialist Robert Owen (1771 - 1858) tried to combine factory production with humane living conditions. The well lit and ventilated factories of his New Lanark mills in Lanarkshire, his company houses for the workers and schools and kindergarten for their children attracted many visitors, including politicians and ministers of the churches, who were all full of praise. But his utopia was exposed to the succession of depression and market recovery like any other factory and could therefore not offer a long-term solution. England's first widespread economic crisis of 1815, caused by a blockade of trade imposed by Napoleon, was followed in quick succession by crisis in 1819 and 1825. (Anderle et al., 1966) The crisis of 1825 was the first of a series of cyclical upswings and depressions that produced mass unemployment and social unrest and resulted from the inherent nature of unregulated capitalism.
The period of Luddite struggle and socialist utopias was relatively short; it ended before the 1820s were over. Only in the colonies could socialist utopias survive somewhat longer. The experiment of José Gaspar Rodríguez de Francia in Paraguay survived for over 50 years before it, too, was violently crushed.
Two new responses developed as the pace of industrialization continued. The working class organized itself into trade unions, and it demanded and progressively gained universal suffrage. The first trade unions arose out of the old organizations of craftsmen. But the growth of the working class - reflected in the rapid increase of the population, which between 1750 and 1800 had grown from 7.8 million to nearly 11 million - required new forms of organization. The foundation of the Amalgamated Society of Engineers in 1851 marked the beginning of the modern trade union movement.
The demand for universal suffrage began with the Chartist movement, the first political organization of the working class. It was named after the "People's Charter" of 1838 that formulated the demands for
The purpose of these demands was to allow ordinary people access to political power and eliminate the bias towards the ruling classes in the counting of votes. The Chartists presented petitions to Parliament in 1839, 1842 (with more than 3 million signatures) and 1848. All three petitions were ignored, some Chartist leaders banished to Australia, others jailed. Real electoral reform did not eventuate until 1867, when the Second Reform Bill granted voting rights to all males in cities who paid at least 10 pound Sterling annual rent, which nearly doubled the number of voters. The Third Reform Bill of 1884 extended the rule to the country, bringing the number of eligible voters from 3 to 5 million. Membership in the Upper House remained (and remains today) hereditary for the aristocracy, but the Upper House lost its right of absolute veto in 1911, when payment for members of Parliament was finally introduced. Women did not gain the right to vote and stand for office until 1919. (Lecture 35)
These developments provided the conditions for a new scientific assessment of the laws of society. Adam Smith's analysis of capitalist society of 1759 could not foresee the development of class organizations. Karl Marx included the new element of class struggle in the analysis. In his work Das Kapital he applied the theory of value to the capitalist economy under conditions of international competition. His analysis has become known as scientific socialism and its application to political theory as Marxism. As a scientific definition the term "socialism" describes a social organization in which property and the distribution of clothing, food and shelter are subject to some degree of social control rather then open to decisions of individuals who follow their own interests. The Inca empire provided an example of early socialism. Its members did not have any private property; their everyday needs were satisfied from state-owned warehouses (Lecture 18). Scientific socialism attempts to formulate the system of social control appropriate for an industrialized society. It restricts social control to the means of production in large industrial conglomerates and leaves it to the individual how to satisfy the needs for clothing, food and shelter.
Marx' theory has created much controversy, mainly because its conclusions reflect adversely on people in powerful positions. It is thus appropriate to spend a few paragraphs on the scientific character of Marxism.
There can be no doubt that human societies evolve and operate according to laws. Science is the activity to discover laws and use the knowledge about them to achieve desirable results. Any attempt to understand the laws of societies and draw conclusions from them is thus a legitimate part of science. Marx drew an analogy to physics in the foreword to his work:
He pointed out that the scientific method requires the study of the basic elements of a process, which can cause intellectual difficulties in political economy, just as it can cause technical difficulties in physics and chemistry:
The scientific study of human societies differs from the scientific study of other nature in one crucial respect. The laws of physics can be applied as they are progressively discovered and understood. Where a law of physics or chemistry is not properly understood one can select not to make use of it in industrial processes until further study allows a better assessment of the situation. (This approach has become known in today's debate about the environment as the "Precautionary Principle.") In the study of the laws of social systems such an option does not exist. Humans have to live together in the society into which their civilizations evolved, whether they understand the underlying laws fully or not. If we were to search for a comparable situation in the science of inanimate nature we might think of an early explorer who has no knowledge of the laws of meteorology but is forced to go on a voyage across the sea: He can take the risk, or he can stay at home and study meteorology first. But the option to stay at home and study the laws of society first does not exist: Societies have to live the best they can and hope to understand their laws as time goes on.
By 1850 Britain was the most industrialized country and the most powerful nation on Earth. Marx used his analysis of England's economical system to predict the development of other countries and the final demise of capitalism. Just as Adam Smith did not foresee the development of trade unions and class struggle, Karl Marx did not foresee the development of 19th century capitalism into the imperialism of the 20th century, a development in which Britain under Queen Victoria's "favourate prime minister" Disraeli participated with colonial annexations in quick succession: 1877 Transvaal, 1878 - 1880 Afghanistan, 1882 Egypt, 1890 Rhodesia, 1898 Sudan.
The annexation of all continents by imperial powers opened the possibility to shift the pauperization of the European working class predicted by Marx to other continents. The immense public debt under which the developing countries struggle today, and which keeps most of their people poor and often close to starvation, is the price the world has to pay for the extension of the time granted to the capitalist society. Any scientific analysis of the world economy shows that the Earth has the means to guarantee all people decent living conditions. Experience shows that this cannot be achieved through an economy based on the laws of capitalism.
Any science that comes to such a conclusion is of course virulently opposed by those who profit from the status quo. It is indeed remarkable that historians of all brands are more or less in agreement with Marxist analysis of feudalism, the slave society and early civilizations but keep their distance when it comes to the analysis of our present society, because it touches on the lives of the scholars themselves: If you admit that your own society is responsible for death and starvation of millions in continents that you cross in a plane when you go to a conference or on a holiday, how do you justify your own lifestyle?
In the 19th century the sciences of the inanimate world did not have to face such uncomfortable questions. The choice between particle stream or wave in a continuum is a choice between two methods that both produce useful results; it is not a choice of ethical and moral dimension. The 21st century shows clear signs that the time of comfort is coming to an end. Science today has become the basis for technological innovations that can make entire countries uninhabitable as a consequence of modern warfare or change the Earth's climate for generations to come. As a result all science now finds itself in a situation where it tries to understand the laws of processes that unfold before our eyes as the result of human action and cannot be stopped. We are crossing an ocean without understanding its weather and hope that the ship will not run into a storm.
Science is no longer aloof from the political controversies of the day. We now witness the emergence of what might be called "partisan science", science moulded to suit the interests of powerful sections of society. Social Darwinism and the population theory of Thomas Malthus were early examples of partisan science. More examples will come to hand as we approach the 21st century.
Accidents can happen and are the result of sloppy science; the invention of heroin is but one example. Weapons of mass destruction and greenhouse gases, on the other hand, are no accidents but results of planned application of science. Partisan science is not sloppy science but wilfully deformed science. It is dangerous because it denies that there is a problem and offers "scientific" reasoning why society is perfect as it is. Lecture 35 will have to discuss partisan science at some length.
Abelès, F. (1965) Instrumental Optics. In: R. Taton (ed.) History of Science, Science in the 19th Century. Basic Books Inc. New York, 144 - 155. (Translation of La science contemporaine)
Anderle et al. (1966) Weltgeschichte in Daten. VEB Deutscher Verlag der Wissenschaften, Berlin.
Cohen, I. B. (1965) Science in the United States. In: R. Taton (ed.) History of Science, Science in the 19th Century. Basic Books Inc. New York, 563 - 570. (Translation of La science contemporaine)
Crowther, J. C. (1967) The Social Relations of Science, revised edition. The Cresset Press, London.
Tonnelat, M.-A. (1965) The theory of light. In: R. Taton (ed.) History of Science, Science in the 19th Century. Basic Books Inc. New York, 156 - 169. (Translation of La science contemporaine)