Sydney - A 97-year-old retired Australian dentist was to receive his masters degree in clinical science on Friday in what Southern Cross University said could make him the world's oldest new graduate.
Allan Stewart, who entered the Guinness World Records in 2006 when he completed a law degree at the age of 91, is graduating in clinical science from Southern Cross University.
This is his fourth degree after completing dentistry in 1936.
He went back to school in his 80s to keep himself mentally active.
Mr Stewart, who was born in 1915, has six children, 12 grandchildren and six great-grandchilden.
He worked as a dentist and earned his second degree in dental surgery.
He finished his third degree in law - typically six years - in less than five because he said that "time was of the essence and I better get a wriggle on in case I didn't make my graduation".
"I think I can hang up my mortar board and academic robes after this one - although I said that after my last degree and then I got bored," Mr Stewart told Agence-France Presse news agency before his graduation ceremony late on Friday in the state of New South Wales.
Mr Stewart said people were never too old to study.
"It is never too late to expand your mind, make new friends and challenge yourself to achieve something worthwhile."
The clinical science masters degree is the fourth degree for the great-grandfather, who began his university studies in the 1930s with a degree in dentistry.
After a long career as a dentist, during which time he became a Doctor of Dental Surgery on completion of his second degree, Stewart decided in his eighties to study law to help keep his mind active.
"As I approached the age of 90 I realized that time was of the essence and I had better get a wriggle on in case I didn't make my graduation," he said.
"So I attended extra summer schools and managed to complete the six-year course in four-and-a-half years, graduating in 2006. Turns out I needn't have rushed."
Stewart, who walks daily and meditates regularly, keeps his mind alert by reading medical textbooks and crime novels and playing bridge.
He enrolled in his latest course in 2009 and said while it had been a "tremendous challenge" he had enjoyed it immensely and would strongly encourage any older people to return to study.
'Never too late'
"People should never use the excuse that 'I am too old to study' or 'I have left my run too late'," he said. "It is never too late to expand your mind, make new friends and challenge yourself to achieve something worthwhile."
Stewart, who had six children and now has 12 grandchildren and six great-grandchildren, is modest about his achievements.
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