JOHN LOCKE died on October 28, 1704, 300 years ago. I have twice given a lecture on Locke. The first time was in 1977, to the staff of the People’s Daily in Beijing. I explained that Locke had the same relationship to the theory of liberal democracy that Karl Marx had to socialism. I can still remember the translator speaking of a character who emerged as “Johnny Lockey”.

The second occasion occurred this month, when I spoke to a large village audience in Publow church in Somerset. Locke was born at his mother’s brother’s cottage in 1632 in Wrington, where there have been other tercentenary celebrations; he was baptised there by Samuel Crook, the local rector. He was brought up on the family property at Pensford, which he later inherited. His father was the agent to the neighbouring Popham estate; there was a descendant of the Popham family in my audience.

Pensford church is closed, so Pensford people go to church in Publow, the neighbouring village. From their questions, I judged that they knew that Locke was a local Somerset man, and that he was a major philosopher, but few of them realised his worldwide influence on political thought.

I told them about Locke’s education at Westminster and Christ Church, Oxford, of his becoming a medical doctor, being employed by the 1st Earl of Shaftesbury, as doctor and secretary, of his going into exile in the Netherlands and returning to England after the Glorious Revolution of 1688. I also told them of his final happy years in the 1690s under the care of Lady Masham in Essex.

The case for Locke’s leading role in developing the political philosophy of liberal democracy is based on the works themselves. Everyone should read them. He had written drafts over many years, but in the early 1690s his flow of publications, each of which is an original masterpiece in its own area, must be unparalleled.

The first Letter Concerning Toleration comes in 1689. It is the briefest of his major works, originally written in Latin, and published in the Netherlands. As he does elsewhere, Locke uses a medical comparison to explain the case for liberty. He writes: “No man can be forced to be healthful, whether he will or no. Nay, God himself will not save men against their wills. Let us suppose, however, that some Prince were desirous to force his subjects to preserve the health and strength of their bodies. What, shall no potion, no broth be taken, but what is prepared in the Vatican or in a Geneva shop?”

Earlier in the Letter Concerning Toleration we have the first draft of what was to become one of the most famous phrases in history. “Civil interests, I call life, liberty, health and indolency of body, and the possession of outward things, such as money, land, houses, furniture and the like.” By “indolency”, Locke meant “freedom from pain”, not “idleness”. Nevertheless, America would have been a very different place if it had adopted an inalienable right to “Life, Liberty and Indolency” — more Homer Simpson than George Washington.

Locke’s greatest philosophical work, the Essay of Human Understanding, was published in 1690. This contained the second half of the famous phrase, though the two parts were only put together by Thomas Jefferson in 1776, when he was drafting the American Declaration of Independence. “As the highest perfection of intellectual nature”, Locke writes, “lies in a careful and constant pursuit of true and solid happiness, so the care of ourselves, so that we mistake not imaginary for real happiness, is the necessary foundation for our liberty.”

That meets the argument that “the pursuit of happiness” is merely hedonist, or no more than what Jeremy Bentham called the “felicific calculus”. Locke is a moralist, who realises that liberty depends on the quality of the choices that free people make for themselves. Bad choices are bad for freedom. Also in 1690, he published Two Treatises on Civil Government, which lays out Locke’s view of the right to revolt against oppression, the equality of all citizens and the contract between government and people. This had the most direct influence on the American and French revolutions. Indeed, almost all subsequent revolutions have started as Lockeian revolutions, however they have ended. People want to be free, but not all revolutions lead to freedom.

As always, Locke’s doctrines remain relevant to modern concerns. He is a political philosopher who never goes out of date. In Book Two of his Civil Government he deals with the limits of legislative power, a text that ought to be framed on the wall of every minister’s office. Locke proposes four boundaries: “First (legislative Power) is not, nor can possibly be, arbitrary over the lives and fortunes of the people . . . secondly the legislative, or supreme authority, cannot assume to itself a power to rule by extemporary arbitrary decree but is bound to dispense justice, and decide the rights of the subject, by promulgated standing laws, and known authorised judges . . . thirdly, the supreme power cannot take from any man any part of his property without his own consent . . . fourthly, the legislative cannot transfer the power of making laws to any other hands.”

This fourth injunction is the reason why it will be necessary to hold a referendum on the proposed European constitution. The people, not Parliament, have the sole right to transfer the power of making laws.

In 1692, Locke published his Considerations of Interest, in which he argues that it is impossible to control prices, either for money, or even for “victuals in a time of famine”. Locke was a free-market economist 80 years before Adam Smith published The Wealth of Nations.

In the 18th century, Locke was the philosopher who inspired the Enlightenment, whose ideas justified the English Revolution of 1688 and the American of 1776, and influenced the French Revolution, before the Terror came. In the 20th century, a 100-year war was fought between liberal Lockeian democracy and totalitarian Marxist socialism. In the 21st century, the ideas of our Somerset hero are prevailing in the global struggle for liberal democracy, three centuries after his death.

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