In the laboratory there are no fustian ranks, no brummagem aristocracies; the domain of Science is a republic, and all its citizens are brothers and equals, its princes of Monaco and its stonemasons of Cromarty meeting, barren of man-made gauds and meretricious decorations, upon the one majestic level!

Herschel made no bones about the fact that a female assistant, even his sister, would cost half as much as a male. It is possible to be indignant about this, but contemporary standards must be taken into account. Female domestic servants were paid £10 per annum, while a highly trained governess like Mary Wollstonecraft was paid £40 per annum by Lord Kingsborough in 1787. In fact a £60 stipend would have been handsome, exactly one-fifth of that paid to the Astronomer Royal. In Europe women who wanted to pursue science, like Voltaire’s beautiful mathematician Madame du Châtelet, or later Marie-Anne Paulze (Madame Lavoisier), simply had to have supportive or (even better) dead husbands, or private incomes. In Britain they had to be schoolteachers or children’s textbook writers, preferably both: like Margaret Bryan (astronomy), Priscilla Wakefield (botany) or Jane Marcet (chemistry). Only in the next generation was it possible to have a career like the physicist Mary Somerville, and (eventually) have an Oxford college named after you. But then, Caroline did live long enough to exchange letters with Mary Somerville drily remarking on this situation.

Since then society has evolved a sequence of ci central con¬ cepts each of which was at one time thought to make it work of itself, and each of which has had to be corrected to the next. There was the early eighteenth-century concept of selfinterest, in Mandeville and others; then came enlightened self-interest; then the greatest happiness of the greatest num¬ bet; utility; the labor theory of valueie; and thence its expression either in the welfare state or in the clasassless society. Men have never treated any one of these conceptpts as the last, land they do not mean to do so now. What has driven them, what drives them, is the refusal to ackno^wledge the concept as either an edict or self-evident. Does this really work, they ask, without force, without corruption, and without another arbitrary superstructure of laws which do not derive from the central concept? Do its consequences fit our experience; do men in such a society live so or not so? This is the simple but profound test of fact by which we have come to judge the large words of the makers of states and systems. We see it cogently in the Declaration of Independence, which begins in the round Euclidean manner 'We hold these truths to be self-evident,'» but which takes the justification for its action at last from *a long train of abuses and usurpations': the colonial system had failed to make a workable society.