Leslie Spoor, who died last month aged 100, was proof that a campaigning spirit need not be worn down by the passing years.
During the 2010 General Election campaign, just five months short of his 100th birthday, Mr Spoor was walking the streets of east Edinburgh, delivering leaflets in a bid to elect Robin Harper as Scotland's first Green MP - in fact the first in the UK.
His long and distinguished involvement with radical politics stretched back to at least 1936 and the Battle of Cable Street, when the then 26- year-old joined thousands of anti-fascists who forcefully prevented Oswald Mosley's British Union of Fascists from marching through London's Jewish East End.
He subsequently joined - and, for many decades, campaigned on behalf of - the Labour Party, during which time he became a close friend of the late Livingston MP and former Foreign Secretary Robin Cook.
Born in South Shields, Mr Spoor studied history at Edinburgh University and settled in the city.
He was, by profession, a history teacher, and eventually became head of his department at Musselburgh Grammar. He also lectured for the Open University and at the then Napier Technical College.
His official retirement in 1975, however, was far from an end; freedom from the day job simply allowed his interest in, and support of, radical causes to flower.
In 1977 he joined the British Ecology Party, and served on its executive committee; the following year, in his front room, he founded the Scottish Ecology Party - now the Scottish Green Party - and organised its first General Election campaign in 1979.
The election of Margaret Thatcher's first government proved to be a demoralising body blow to the nascent party which, during the 1980s, remained very much a fringe force in Scotland, with just a three-figure membership and fewer than 5,000 votes across the country. Nevertheless, Mr Spoor and numerous family members continued to campaign on "green" issues. He took some pride in the election of Robin Harper to the Scottish Parliament in 1999.
Arguably, it was Mr Spoor's own longevity that most informed the passion for ecological and environmental issues that dominated the latter third of his life. Only last year he told journalists: "In a long and active life, I have seen political fashions come and go, and when you have such a wide perspective, you realise that what matters is long-term vision."
His friend and Green Party colleague Gavin Corbett said of him: "This is someone who became involved in political activism when fascism loomed over Europe in the 1930s and was still active in the 21st century, when we face many different challenges. He was a generous and kind-hearted man and that won him friends across the political spectrum."