THe third US president, Thomas Jefferson is often said to have owed his pre-eminence as a political philosopher in large part to William Small, his Scottish tutor at the College of William and Mary in Virginia.

Jefferson, born in 1743, studied there in 1762-4 and from the start impressed the institution. He proceeded to qualify as a lawyer before launching his political career as a member of Virginia’s House of Burgesses from 1769.

The revolutionary era was about to burst on the American colonies, but during this first stage Jefferson did not appear to find his Scottish learning especially useful.

On the contrary, when the rebel delegates called the Continental Congress to Philadelphia in 1776 and put Jefferson in charge of drawing up the Declaration of Independence, he identified Scots as enemies.

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In an early draft he accused the government in London of sending out “Scotch and foreign mercenaries” to deluge the colonists in blood. Strong stuff – but the eloquent agitator could not get it past older and wiser heads deliberating with him in Philadelphia.

The offending phrases on Scotland were taken out of the final text at the insistence of the Rev John Witherspoon, himself a Scot and president of Princeton University.

He was also a representative of New Jersey, the only clergyman to sign the declaration and one of only two Scots. Weighty figures such as him were not to be led astray by displays of youthful eloquence.

Still, if these were the attitudes to Scots at the highest revolutionary level, it rather makes a mockery of the assumption in older generations of historians that there was widespread Scottish support for the overthrow of colonial status. In fact, the sole prominent Scot never to doubt the justice of the American cause was Witherspoon himself.

This radical minister of the Church of Scotland had been born in 1723 at Yester in East Lothian, a son of the manse. He studied at the University of Edinburgh.

A fellow clerical student, Alexander Carlyle, remembered him as “very sensible and shrewd, but of a disagreeable temper, which was irritated by a flat voice, and awkward manner, which prevented his making an impression on his companions of either sex”.

He was in Carlyle’s view a jealous man, which “made him take a road to distinction, very different from that of his more successful companions” – in other words, rather hostile to the powers that be in Scotland.

Another student of the rising generation, John Home, left a similar unflattering portrait of Witherspoon during the Jacobite rebellion of 1745. Witherspoon had by that time completed his studies and become minister of Beith in Ayrshire.

He organised a company of volunteers from the district to go and fight for the Hanoverian succession against the Jacobite army. In January 1746, he was captured while observing the Battle of Falkirk, and imprisoned in Doune Castle.

Witherspoon moved to be minister of the Laigh Kirk in Paisley in 1758. During his two pastorates he wrote works on reformed theology, seeking to blend it with the Common Sense realism that was emerging as the mainstream philosophical school in Scotland. To his serious books he added a satire, Ecclesiastical Characteristics, on how the Kirk was being run by a clique of conservative ministers.

The National: George Washington (left), the first president of the US, was a frequent visitor to Witherspoon’s country estateGeorge Washington (left), the first president of the US, was a frequent visitor to Witherspoon’s country estate

The list of publications made Witherspoon one of the most visible ministers on the radical side of the Kirk. His reputation spread all the way to America, where efforts were under way to give Presbyterians a more robust organisation. It included a small college to train ministers, which was to become Princeton University in New Jersey. Witherspoon was invited over in 1768 to become its principal.

The American colonies would then have a Scottish university in their midst and by the turn of the century it was the most prominent in reputation and popularity of the prerevolutionary colleges (later known as the Ivy League).

Witherspoon became an active principal, himself teaching history, divinity, eloquence and moral philosophy. At a personal level, he grew much richer than he could ever have expected as a Scottish country minister.

In 1773 he acquired near Princeton a country estate, Tusculum. George and Martha Washington often came to visit.

Material comfort gave Witherspoon the standing to join in the controversies of the day.

One was over Scottish emigration to America. The British government was not too keen on this because it wanted to reserve lands in the West for indigenous tribes that had been its allies in recent wars.

Witherspoon took the American view that, as the flow of settlers across the Atlantic Ocean grew, there were profitable investments to be made in territories such as Nova Scotia and New York, where the days of indigenous occupation were clearly over.

By development, benefits would accrue not only to emigrants but to the whole of a North Atlantic trading system.

For similar reasons, Witherspoon favoured slavery. New Jersey never was a colony with a slaving economy and did not legally free its slaves till 1865, largely because of his influence. In his time, slaves still worked on plantations, on country estates, on small farms and even in urban businesses.

As a citizen, Witherspoon was entitled to benefit from this and he owned slaves himself. He publicly lectured and voted against the abolition of slavery in New Jersey. At the same time, he maintained a commitment to the religious instruction and general education of black slaves. The contradiction meant little to him.

As trouble between Britain and the 13 colonies worsened, Witherspoon’s commitment to the American side strengthened. An early publication of his was Thoughts on American Liberty (1775).

The next year he published a sermon, The Dominion of Providence over the Passions of Men, again defending the American cause. He added to the published version an Address to the Natives of Scotland Residing in America, urging them to identify with the revolutionary effort.

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Princeton became a hotbed of political radicalism. In his teaching, Witherspoon advanced a number of ideas that were about to become important in the US, as the new nation drew up a constitution for itself.

He argued for a revolutionary right of resistance but recommended that government should be limited by a system of checks and balances.

On religion, he taught that every human being, Christian or otherwise, could become virtuous, though only Christians might expect personal salvation.

Nine of Princeton’s graduates sat in the convention which at length drew up the US Constitution. James Madison, who had studied under Witherspoon, was its main author.

There was plenty for them to discuss in their teacher’s somewhat eccentric collections of opinions but revolutions probably need people like him.