People in a valedictory mood are fond of suggesting they have left their place or position in much better shape than how they found it.
Sir Robert Muldoon said that about New Zealand in a 1984 farewell speech that forever defined the limits of high irony.
But the intention to improve the world remains entirely valid.
When I surveyed the skills I had as a teenager, a sprawling road map of infinite possibility, I thought the question was not whether I would improve the world around me, but in which way.
But these fraudulent high school skills were soon exposed as bedroom dreams, and there is now only one way I can see myself having made the world around me a better place - the jokes I write annually for the Colbert Christmas Dinner Crackers.
Nineteen this year, as many as 30 in years gone by.
These jokes differ from two-dollar shop Christmas cracker jokes because they are totally original, drenched in intellectual property purity.
If you claim to have heard any of these before, I will beat your price by 15%.
Writing a shockingly bad Christmas cracker joke is harder than you think, but at least you have intellectual cover.
Nobody laughing may frighten the stand-up comedian, but it soaks the original Christmas cracker writer in triumph.
This year, I took all the jokes from the animal kingdom, the suggestion being that I could just as easily have written all 19 from the world of Portuguese pencils.
A hint of smart never hurt a bad joke.
Let us look at a wincing selection that came out of the crackers last Saturday evening.
What breed of dog will never get a warrant of fitness? A rot wheeler.
I felt this was quintessential Christmas cracker fodder and settled back in my chair for a warm round of applause.
It never came.
Possibly something was lost in translation.
The second-year university student said dogs don't go for a warrant of fitness, but I was a bit of a pedagogue myself at that age, so I let that one slide by.
Which mammal spends the most time at the vet? A poor puss.
Quintessential again, but I wasn't quite hitting the spot, tough crowd.
So I brought out the big stuff.
What do you call a mammal whose benefit has been cut off? A dole fin.
A few faces screwed up at this bi-lingual doozie, someone else said, "What did he say?".
It seems even on Christmas Day when the spirit of forgiving runs like the mighty Manuherikia, nobody likes a clever dick.
Which is the most romantic and daring insect? An ant elope.
Very good, said the 89 year-old father of the wife, who still effortlessly knocks over the Christchurch Press cryptic crossword; are we having dessert, asked the 4-year-old grandson from Chicago.
I was nearly done.
Had I made anyone's world better? There had been laughter, but a raft of empty Sacred Hill sauvignon blanc bottles littering the table like unsuccessful race tickets might have done that.
I was forced to play my last card, the one Close Up and Campbell Live all mine shamelessly to prop up their sagging television shows.
Tears.
Which is the best dog to be with at Christmas? Holly.
This oblique lateral animal mixed metaphor stupefied most of the table, but I looked across at my wife and saw the tears forming.
Holly was our dog, mad as a raisin for 15 years until the vet's injection mercifully closed her down on our lounge floor.
Holly never gave you the feedback you crave from a dog.
If you put your arm around her, she would go and sit behind the sofa.
Her Seroquel expression never changed, whether you gave her rib-eye steak or accidentally poured custard on her head.
We loved her beyond tears.
We remembered Holly at her 15 Christmases, and in that frozen moment, the memory made our world a better place.
• Roy Colbert is a Dunedin writer.
