He wrote: "I am having such a wonderful day on the tubes I can't not share this story.
"Let me build the scene: Central Line between Oxford Circus and Chancery Lane, possibly St Pauls.
"To my right is sat a lady, 25-30, wearing a revealing dress. To my left is an old lady, almost dead is how old she is. Standing in front of us is a man, 50's, suit and tie, eyeing revealing dress.
"Suit leans over to the revealing dress lady and says 'Have some self respect when you dress yourself'."
Scott continued: "Revealing dress lady blushes to the colour of her almost not there dress.
"Old soon to be dead lady is having none of this and in a south London accent shouts out 'She can wear or not wear whatever the f*** she likes.
"'Even if she was naked with a sign pointing to her f***y (she said f***y on the central line by St Pauls) and the sign pointed to her f***y which said ...PARTY CITY ALL INVITED...then that would still be none of your bloody business.
"'Now f*** off back to your bored wife!' Red dress then hugs the walking dead and old suit walks off.
"That old lady will be my hero for the rest of her life, even if the rest of her life is like only another week. She was so old."
The post has delighted thousands of people who have shared the post on Facebook at Twitter.
One woman called Sophie Addyman said: "This has made me properly belly laugh. Well done old Lady! You tell him!"
Another called Rosalind Lambert-Porter added: "I'm now going to ride the tubes dressed as a really old lady so I can shout at the travelling p***ks and get away with it."
Sexism and abuse on the tube has been a long-fought problem in London.
Last April, Transport for London launched a campaign to tackle abuse on public transport, with a video in which a female commuter is groped while on the Tube.
The uncomfortable footage - which uses actors - sees the woman hounded by an increasingly persistent male, who looks her up and down, gets on to the same train carriage and then gropes her.
Every time the man steps up his creepy efforts, the narrator - Broadchurch actress Olivia Coleman - asks: "Would you report it?"
After the man, who is clearly wearing a wedding ring, gropes his victim, she moves to a separate part of the carriage, only for him to shuffle up behind her.
"He pushes his groin right into you," the narrator says. "Would you report it?"
According to TLC, one in ten Londoners have experienced unwanted sexual behaviour on public transport, but 90 per cent of these incidents go unreported.
The campaign's website reads: "You can report anything of a sexual nature, including rubbing, groping, masturbation, leering, sexual comments, indecent acts, or someone taking photos of you without your consent."
- Daily Mail