One of the most enduring and influential innovations was the metre. Under the old system, there were in France an incredible 250,000 different units of weights and measures, though the most widely used unit of length was the pied, held to be equal to the length of the king’s foot, and this had other uses – for example, the ‘point’ in printing, which was 1/144 of a foot. Perhaps nothing could have been more incendiary than this in a revolutionary context, even though, in this instance, the events of 1789 only precipitated reform that had been talked about since 1775, when the chief minister, Turgot, had asked Condorcet to draw up a plan for a scientific system of weights and measures based on the one-second pendulum. This went back to Galileo, the idea being that the basic unit of length should be the distance a pendulum swung when beating for one second (this was Talleyrand’s idea). But there were too many problems associated with this, mainly having to do with the fact that the earth is not a perfect sphere, being flattened at the poles and bulging at the equator. Even Newton had been aware that gravity varies slightly with latitude, and not consistently, so that the swing of a pendulum is more erratic than one might think. The next proposal was to base the unit on something from nature, and a commission appointed by the French opted for a measure of the circumference of the earth, in which everyone had a stake. The commission calculated that a measure equal to the circumference divided by 40 million would give a value very near the aune of Paris, a familiar three-foot length comfortably on the human scale.5 This proved popular, the more so as it could be seen as the basis for a far more rational system of measures: a gram would be one cubic centimetre of rain water weighed in a vacuum at the temperature of maximum density (4° C); a franc would be 0.1 grams of gold, divisible into 100 centimes. All this came to pass, save for the decimalisation of time: the new calendar which named twelve months of thirty days – again after nature – never caught on (Brumaire, the month of fog, Thermidor, the month of heat, Ventôse, the month of wind), nor the practice of dividing days into ten hours and hours into a hundred minutes. People never got used to the idea that five o’clock was mid-day, or that ten o’clock was midnight, and the system was ignored.
But the metre was important for more than itself. It occasioned a celebrated experiment, or seven-year survey, when two men, Jean-Baptiste-Joseph Delambre and Pierre-François-André Méchain, mapped the meridian from Dunkirk to Barcelona (passing through Paris), which determined the exact length of the circumference of the earth, on which the metre measure was based. The survey led to the first international scientific conference, in 1799, to consider collaboratively the evidence produced by Delambre and Méchain and to decide on the definitive length. Ironically, the survey produced a set of errors which, because of their importance, formed an important stage on the way to the invention of sophisticated statistics, which are discussed later in this chapter.6 The length the two men calculated for the circumference of the earth differs from modern-day satellite surveys by less than eight pages of this book.
But the most shattering aspect of the aftermath of the events of 1789 was of course the Terror, followed by the Directorate and the Consulate. This suggested to many that the old oppression had merely been replaced by a new kind. For still others, the aftermath merely reinforced the view that man’s true nature was as savage as it was wicked, vengeful as it was baleful, justifying the need for absolute authority in both the temporal and spiritual realms.7 A third reaction was different again. This view held that the revolution had got out of hand because while some people had been eager to put liberty before order, for others the priority was the other way round, order before liberty. What was the best form of order to maximise liberty? This was one of the founding sentiments which gave rise to the idea of sociology.
Roger Smith notes that it was the French revolutionaries who described change as l’art social, and that one of the first references to la science sociale came in a tract by the abbé Sieyès, What is the Third Estate?, which tried to identify what, exactly, was ‘the commons’ in France, in contrast to the monarchy, or the nobility, or the church. La science social was, in the mind of Sieyès and others who came after him, in effect a new stage in thought, a step on from the idea of a secular world, because men were now considering social organisation, social order, without resort to political grouping.8 Condorcet, who among other things was the permanent secretary of the Académie des Sciences (and had been in hiding, under threat of the guillotine), took up Sieyès’ phrase on the founding of the Société de 1789, the specific aim of which was the social reconstruction of France using les sciences morales et politiques. Although the Société did not outlast Condorcet’s death, in prison, the ideal of a science of society lived on and, following the reform of the universities and grandes écoles in 1795, the Classe des sciences morales et politiques at the new Institut National had a department named Science sociale, et législation.9
It was not at all surprising that la science sociale should prove popular in France. After the Revolution, the French nation was no longer composed of ‘subjects’ but of ‘citizens’, which, it was felt, meant learning a new way of living together. This was made all the more pressing because citizens of both the left and the right (terms which were first used to reflect the seating plan in the French Constituent Assembly after 1789) felt the need for something new.10
If Sieyès and Condorcet were the first to coin the term ‘social science’, the first social scientist worth the name, at least in France, was Claude-Henri de Saint-Simon (1760–1825). He had fought for the Americans in the War of Independence, and was therefore well aware of how the young republic was using Enlightenment ideas, where appropriate, to bring about democracy, science and progress, and, like many Frenchmen of his generation, he was much taken with the recent advances in mathematics and the natural sciences. The contrast that he saw about him between their steady advance and the mayhem and aimlessness of political manoeuvring pushed him in the direction of la science sociale. This progress of the sciences, and the general optimism which they brought with them, caused him to introduce the term ‘positive’ to describe those activities of man that had finally eliminated any reliance on metaphysical explanations. Following the Revolution he thought that the science of man would become more and more positive, especially if physiology continued the progress it appeared to be making. He believed there were regularities, patterns, to be found within ‘the concrete conditions of social life such as climate, health, diet and labour’. He became convinced that there was organisation in life that had nothing to do with politics (or theology, come to that). For Saint-Simon, medicine was a better metaphor for this organisation of society, and physiology in particular. He began to ask whether there might be laws governing social conduct, of which we are unaware, just as at one time the principle of the circulation of the blood was unknown.11