Question:
One man shows another the portrait of a gentleman and tells him: I have neither brothers nor sisters, but this man's father is the son of my father. Who is the man in the painting?
Answer:
The gentleman in the portrait is the son of the man who is speaking.
Try another Brain Teaser:
A man was outside taking a walk, when it started to rain. The man didn't have an umbrella and he wasn't wearing a hat. His clothes got soaked, yet not a single hair on his head got wet. How could this happen?