A Dutch "positivity trainer" has launched a legal battle to change his age and boost his dating prospects.
Emile Ratelband, 69, wants to shift his birthday from 11 March 1949 to 11 March 1969, comparing the change to identifying as being transgender.
"We live in a time when you can change your name and change your gender. Why can't I decide my own age?" he said.
A local court in the eastern city of Arnhem is expected to rule on the case within four weeks.
However officials were sceptical about the case, believing there was no legal mechanism allowing a person to change their birth date, local reports said.
One of the judges wanted to know what would become of the 20 years that Mr Ratelband wanted to erase. "Who were your parents looking after then? Who was that little boy?" he was quoted as saying.
'Making the most of life'
Mr Ratelband argues he feels discriminated against because of his age, and that it was affecting his employment chances and his success rate on the dating app, Tinder.
"When I'm 69, I am limited. If I'm 49, then I can buy a new house, drive a different car. I can take up more work," he said.
"When I'm on Tinder and it says I'm 69, I don't get an answer. When I'm 49, with the face I have, I will be in a luxurious position."
Mr Ratelband further argued that according to his doctors he has the body of a 45-year-old, and described himself as a "young god".
He went on Facebook last year to describe how he had made the decision one day standing in front of a mirror, not because he feared getting old but because he wanted to make the most of life for as long as possible.
He also said he would renounce his pension if he switched his birth date.
Mr Ratelband, a media personality and motivational guru, converted to Buddhism earlier this year and is a trainer in neurolinguistic programming.
He voiced the character Vladimir Trunkov in the Dutch-language version of the Pixar film Cars 2.