Sir Patrick Geddes

Best known for redefining - some would say inventing - the concept of modern town planning, many claim today that Geddes has been overlooked as one of the most important thinkers of the Victorian era.

But the zoologist, botanist and eventual philanthropist's abiding contribution to history remains the regeneration and conservation of Edinburgh's Old Town.

Patrick Geddes was born the son of a soldier, in Ballater, on 2 October 1854. Educated in Perthshire, Geddes rose from his humble upbringing to swift recognition by The Royal Society, which published his biological research papers when he was aged 25.

The following year the British Association for the Advancement of Science employed him to set up a zoological station in Stonehaven, Aberdeenshire. Later the association sent him on a research mission to Mexico where illness caused him to temporarily lose his sight and threatened his scientific work by causing him eyestrain when using a microscope.

Geddes went on to work extensively in America, France and India. Much of his work focused on closing the divide between Scotland and the sub-Continent, and indeed the arts and sciences. Geddes would plan dozens of cities in the rapidly industrialising former colony, while becoming a close confidant of Mahatma Gandhi.

As a young planner he organised a series of international exhibitions alongside Central Park designer Frederick Law Olmsted, which taught that good planning always gives priority to the well-being, both physical and mental, of the inhabitants.

Geddes wrote: "The world is mainly a vast leaf colony, growing on and forming a leafy soil, not a mere mineral mass: and we live not by the jingling of our coins, but by the fullness of our harvests."

Though Geddes never completed a formal degree, he was appointed to a Chair of Botany at University College Dundee in 1889 and later professor of Civics and Sociology at Bombay University. He was awarded the International Gold Medal for Sociology in Ghent, in 1913.

Well thought of by his academic peers, Darwin wrote to Geddes: "I have read several of your biological papers with very great interest, and I have formed, if you will permit me to say so, a high opinion of your abilities."

Meanwhile, Einstein would write: "I have heard much praise from my Jewish friends concerning Mr. Geddes's work and personality. All who know him admire and honour him highly."

Although well travelled, studying in Palestine and France, it was a short move in Edinburgh - between 81a Princes Street in the New Town to 6 James Court in the Old Town - that would produce Geddes's most lasting legacy.

"Geddes moved at a time when the Old Town was a slum," says David McDonald, a director of Edinburgh's Cockburn Association. "In the 18th century most people in the better paid professions moved from the Old to the New Town.

"As the political importance of the capital diminished in the 19th century, so the Old Town fell into disrepair. While the hub of the Enlightenment was the New Town, Geddes set about reviving the Old Town."

Geddes would regenerate and protect over 70 sites, including Lady Stair's Close and Mylne's Court alongside many of the Royal Mile closes and wynds. He also transformed Moray House from a ruin into a teaching college and founded the Camera Obscura outlook post above the city.

He was a co-founder of the Social Union, which was passionately interested in encouraging public art such as murals. He also edited a magazine, The Evergreen, which showcased both art and poetry. Geddes was also influenced by the ideas of neo-romanticism and Celtic revivalism, through which he contributed to the role of Scottish nationalism.

Noting that Geddes served on the Cockburn Association's board of governors for 21 years, McDonald explains: "Geddes did not just preach renewal, he was out there participating - gardening and cleaning closes. It was all part of improving people's confidence, life and health."

Many sites stand testament to Geddes's work, notably Pittencrief Park in Dunfermline, his biggest piece of commissioned work, which Geddes gifted to the town in 1904. Much of his later work was in collaboration with his son-in-law, the architect, Sir Frank Mears.

Having once turned down a knighthood - McDonald explains, because "Geddes was a man of the people" and also, noting less seriously, that Geddes believed the title would "increase his hotel bills along the way" - Geddes assented to becoming a knight shortly before his death in 1932, in Montpellier.