The name Andrew Duncan is well known in Scottish medical circles, but did you know he was also in a sex society?

EDINBURGH, in the age of Enlightenment, was a city in which residents could doff their hats at 50 men of genius in a single day.

• Andrew Duncan in a portrait by Sir Henry Raeburn, courtesy of the Royal College of Physicians of Edinburgh. Picture: Complimentary

Andrew Duncan was not, according to his biographer, one of them. This is not to say he was a stupid man – far from it – merely that in the late 18th and early 19th century, the bar was set so high that only giants of the intellect could hope to clear it.

Anyway, the good Dr Duncan was too busy helping people and having fun in a manner that would have a Calvinist clench their fists with fury.

Today, the son of a Fife shipmaster is celebrated for two revolutionary acts of social medicine: the founding of a dispensary for the sick poor and a lunatic asylum where inmates were treated humanely.

Yet such was his passion for life that he achieved much more than that, as John Chalmers' new book, Andrew Duncan Senior: Physician of the Enlightenment makes clear.

A careful reading reveals a man whose company it would have been a pleasure to keep. Take, for example, the many clubs and societies he founded, such as the Aesculapian Club.

The name derives from the Greek god of medicine, the son of Apollo, and was designed to foster goodwill and fellowship between physicians and surgeons, whom they regarded as a lower status.

Meetings began promptly at 4pm with a brief medical discussion, before a feast of epic proportions at 5pm. One menu records the evening meal as "roast fowl, rice, fish, curried chickens, crabs, sallad, cold lamb, apple pye, mock turtle, potatoes, eggs and gravie, lobster, spinage minced pies, roast lamb, and ham". All washed down with wine, brandy, gin, whisky, port and sherry.

He also founded the Harvein, Gymnastic and Royal Caledonian Horticultural societies and, despite being happily married to Elizabeth Knox, who would bear him 12 children, once replied to a toast by stating that 1771 was a memorable year because not only was he married then, but he was also created a knight of that most ancient order of merit, the Beggar's Benison, a society dedicated to sex.

But, as Mr Chalmers, a retired orthopaedic surgeon who has compiled a new book of essays on Duncan makes clear, readers should not imagine cavorting wenches but the recitation of bawdy verse.

"They did not bring in prostitutes or engage in any sexual activity," he says. "I'm not sure to what extent active sex even featured in club activities.

It was an extraordinary reflection on this time in Edinburgh when one of the features of the Enlightenment was an attempt to discard the Calvinist inhibitions in society that had been present. I found that extraordinary, that these sex clubs should have existed perfectly openly.

They advertised the meeting and reported their council meetings in newspapers. The one which Duncan joined – the Beggars Benison – was a society that started up in Anstruther and Edinburgh, Glasgow and even St Petersburg, and had local lairds and clergy as members. The Prince of Wales was a member of the Beggars.

I think to some extent these places reflected the liberation from the Calvinist inhibitions and reflected the morality of the monarchy."

Life, in all its forms, was celebrated by Duncan, who was also a keen golfer, an avid walker who climbed Arthur's Seat every May Day until his death in 1828 at the age of 83, and an enthusiastic practitioner of very poor poetry. Although he planned to write a poetic autobiography divided into seven cantos, fate was kind and only the first survives. It includes the lines:

At Pinkerton I first drew breath,

And breathe I must until my death,

With Sandy Don I went to school,

Like other boys to play the fool.

In one way, it was a passion for poetry and the plight of one of its finest practitioners that led to the founding of the Edinburgh Lunatic Asylum. As a young doctor, Duncan had attended the poet Robert Fergusson, who, in 1773, at the age of only 24, began to develop signs of insanity which took the form of "religious melancholia".

Fergusson began to obsess on what he regarded as his misspent youth and to suffer hallucinations, which worsened after he fell down stairs. As his mother was unable to look after him, he spent the last two months of his life in a bedlam.

Duncan later wrote: "I found him in a very deplorable condition, subjected to furious insanity. He lived in the house of his mother, an old Widow in very narrow circumstances.

Her feeble and aged state… rendered it impossible to make any attempt towards cure, with the slightest prospect of advantage, while he remained at home. After several fruitless attempts to have him placed in a more desirable situation, he was at last removed to the Bedlam of the City of Edinburgh.

"There also I continued my visits to him in conjunction with my late worthy friend, Mr Alexander Wood, who had at that time charge of the Medical Department of the Edinburgh Poorhouse and of the Bedlam attached to it.

Without a convalescence from his insanity, death soon put an end to poor Fergusson's existence… His case, however, afforded me an opportunity of witnessing the deplorable situation of Pauper Lunatics even in the opulent, flourishing, and charitable Metropolis of Scotland… Since that period… my feeble endeavours have been steadily directed to the erection of a well constructed Lunatic Asylum in Edinburgh; and it is with some satisfaction I can say that these endeavours have been attended with at least some benefit to the unfortunate Maniacs in Edinburgh."

In 1790, when Duncan became president of the Royal College of Physicians, he proposed the founding of a lunatic asylum, but despite the support of the college and council, work was slow. It was not until 1809 that the foundation stone was laid on four acres of Morningside land purchased for 1,420, and four years later that the first patient was admitted.

Mr Chalmers explains: "At the time, there was no speciality of psychiatry, there was no doctor who could treat them. His objective was to create a benign and civilised setting where these poor individuals could come to be accommodated.

The only accommodation for the insane prior to this was in bedlams, which were like prisons. They were very uncomfortable – the Edinburgh bedlam was 20 bare rooms with straw on floor where people lay without even the protection of windows."

The inspiration for this book came to Mr Chalmers while researching a previous tome on James John Audubon, the French-American ornithologist who lived in Edinburgh while illustrating his comprehensive book, Birds of America. In his journals, Audubon had written of his delight when Andrew Duncan came to an exhibition of his paintings.

Mr Chalmers, who is 82 and spent his professional career at Edinburgh Royal Infirmary and the Princess Margaret Rose Hospital, says: "Like anyone in Edinburgh, I had been aware of the name of Andrew Duncan in connection with the Edinburgh mental hospital, but a few years ago I kept coming across the name of Andrew Duncan in other contexts. Then I became a member of the Aesculapian society and discovered Duncan had been the founder. His name kept popping up.

"What I admired about him was his persistence. If he thought he had a good idea, he pursued it relentlessly, regardless of what opposition he encountered, and eventually he would achieve his objective. He had great concern for his fellow man. He tried his best to improve the lot of the underprivileged in society."

Just as his book on Audubon inspired this one about Andrew Duncan, so Duncan has inspired his next book. "I'm working on an account of an interesting duel which took place between Sir Alexander Boswell – James Boswell's oldest son – and James Stewart, which is briefly mentioned in this book. It took place in Fife in 1821 and resulted in Boswell's death."

Curiously, death was not considered by Duncan to mean an end to one's labours, simply a new location in which to toil, as this poem, written five years before his own death, testifies:

And you, good Doctor, with your last breath,

Shall feel your ruling passion strong in death;

Just in that moment, as in all the past,

Improve my country, Heaven, shall be your last.

• Andrew Duncan Senior: Physician of the Enlightenment, edited by John Chalmers, is published by the National Museums of Scotland, priced 14.99.