No straightforward connection can be drawn between the union and the exceptional 18th-century flowering of intellectual life known as the Scottish Enlightenment. Absence of civil strife, however, permitted the best minds to turn, if they chose, from politics and its 17th-century twin, religion, and few of the best minds from 1707 onward were in fact directly concerned with politics. Philosophy, in which 18th-century Scotland excelled, was a proper concern for a country where for generations minds had been sharpened by theological debate. Scottish culture remained distinctive, and distinctively European in orientation. The historian and philosopher David Hume sought to remove Scotticisms from his speech, and the architect Robert Adam gained extra experience as well as income from being able to design buildings in London as well as in Edinburgh. Nevertheless, Adam drew most of his stylistic inspiration from the Classical architecture he had studied in Italy, and Hume, “le bon David,” was an honoured member of Continental polite and intellectual society. Hume’s The History of England (1754–62) made his literary reputation in his lifetime, but it is his philosophical works, such as his A Treatise of Human Nature (1739–40), that have caused the continuous growth of his reputation since his death. Adam Smith, author of The Wealth of Nations (1776), was the philosopher of political economy. The discipline of history was developed by William Robertson, a Church of Scotland clergyman, principal of the University of Edinburgh, and official historiographer royal for Scotland; his History of Scotland, During the Reigns of Queen Mary and of King James VI was published in 1759. Henry Home, Lord Kames, may be singled out from a number of other significant figures to illustrate the versatility characteristic of the times. He was a judge, interested in legal theory and history, an agricultural reformer in theory and practice, a commissioner of the Forfeited Estates (of the rebels of 1745), and a member of the Board of Trustees for Manufactures (which encouraged Scottish industries, notably linen production). In poetry there was a reaction, possibly against union—and certainly against assimilation—with England; revived interest in Scots vernacular poetry of the past was the herald of a spate of new vernacular poetry, which culminated in the satires of Robert Fergusson and the lyrics of Robert Burns. Some of the greatest Gaelic poets, such as Alexander MacDonald, were also writing at this time.

The Scottish educational system, its foundations so securely laid throughout the previous century, made possible this extraordinary cultural outpouring. The Scottish universities enjoyed their heyday, Edinburgh being notable for medicine and preeminent in most other subjects as well. Gradually the regents, who taught students throughout their university course, were replaced by professors specializing in single subjects. That students seldom troubled to graduate was of little disadvantage in an age when appointments depended on patronage. Not bound by a rigid curriculum, students were able to indulge the Scots’ traditionally wide intellectual curiosity by attending lectures in a variety of subjects. Scientific study was encouraged, and practical applications of discoveries were given due place. Francis Home, professor of Materia Medica at Edinburgh, studied bleaching processes and plant nutrition; and James Watt, instrument maker to the University of Glasgow for a time, was encouraged by the university to work on the steam engine, to which he was to make crucial improvements.