What do you see - an old crone or a beautiful elegant lady (replete with Edwardian hat)? Is the glass half full or half empty?
The Christmas story of Ballymagroarty priest Fr Paddy O'Kane is a kind of popular psychology test to show us our true character.
On the Sunday before Christmas, a man in a dishevelled state turned up at the parish priest's door about five o'clock in the morning.
According to Fr O'Kane, the visitor looked in a bad way. Being a kind man, he took in the bedraggled man, got him dry clothing and listened to his story.
The priest is in no doubt that the man was desperate and suicidal: "I believed his story that he was going to take his own life - I have had depression myself in the past and I would recognise the symptoms."
After having a good night's sleep, the mystery man left, thanking the priest for his kindness and assuring him that he had saved his life.
Reassuringly for the cynics of this world, it was discovered after he left that he had taken a sum of money from the PP's office.
After initial anger, Fr O'Kane - convinced that the man wasn't simply a con artist - gave way to compassion: "I see his stealing from me as an act of desperation. With God's help he can make a new start. I saw a lot of goodness in this man."
The cynics may sneer and feel vindicated by the tale. But Fr O'Kane's simple goodness and decency reminds us that there has to be more to life than caution, calculation and fear.
To be fully alive you sometimes simply have to trust - even at the cost of seeing it abused.