Hardie was born on at New Spynie near Elgin, Morayshire, Scotland, son of John Hardie, farmer, and his wife Margaret (née Masson). She was the daughter of Alexander Jeans and Isabella Blythe. His eldest daughter M.I.H. Hardie, (known as Helena) was born in 1886 at Forres.
He attended school in Elgin before furthering his education at the University of Aberdeen (Bachelor of Medicine, Bachelor of Surgery, 1878), he worked there for two years as a demonstrator in anatomy, then started general practice in 1880 at Forres, Morayshire.
They soon after settled in Brisbane and he was registered in Queensland on 5 May 1887. Living initially at Stanley Villa on the south bank of the Brisbane River, he settled finally in Wickham Terrace. In 1893, David"s youngest daughter (and biographer), Jean Blythe Scot Hardie was born.
In 1893, he became president of the Medical Society of Queensland, which became a branch of the British Medical Association, the predecessor of the Australian Medical Association.
In 1902 he built Firhall in Wickham Terrace where he resided and practised. Hardie was a capable family physician and popular with patients in all levels of society.
He joined the Royal Army Medical Corps and served with it in France in 1915-1916. He was an honorary physician for years to the Hospital for Sick Children, the Lady Bowen Hospital and the Lady Lamington Hospital and also served on the Central Board of Health from 1894 to 1915 and the Medical Board of Queensland from 1894 to 1934.
He published numerous journal articles and one book in 1893, Notes on Some of the More Common Diseases in Queensland in Relation to Atmospheric Conditions.
Hardie retired from active practice in 1922 and investigated the treatment of tuberculosis in England and Switzerland in 1922 and 1923 on behalf of the Queensland government. In 1927 he became a founding fellow of the (Royal) Australasian College of Surgeons. He helped form the Review
John Flynn"s Aerial Medical Service of the Australian Inland Mission from 1928 and fostered the development of Alfred Traeger"s pedal radio.
Sir David Hardie died in Brisbane and was cremated. His patients had ranged from the vice-regal to the humblest citizen.
He was awarded the Military Cross during his medical war service in World War I.
