Theres no trick, just pure logic.

1-     There are 5 houses in a street and each house is a different colour.

2-     In each house lives a man, each of whom is of a different nationality than his neighbours.

3-     Each man has a favourite drink, has his favourite brand of cigarettes ands owns a pet.

4-     No two men drink the same drink, smoke the same cigarettes or have the same pet.

Question:   Who has a goldfish?

Clues:

• The English man lives in the red house.
• The Swedish man has a dog.
• The Danish man likes to drink tea.
• The green house is to the left of the white house.
• The owner of the green house drinks coffee.
• The man who smokes Pall-Malls has a bird.
• The man who lives in the house in the middle drinks milk.
• The owner of the yellow house smokes Dunhills.
• The Norwegian lives in the first house.
• The man who smokes Marlboros lives next to the man who has a cat.
• The owner of the horse lives next to the man who smokes Dunhills.
• The man who smokes Winfields, drinks beer.
• The Norwegian lives next to the blue house.
• The German smokes Rothmans.
• The man who smokes Marlboros has a neighbour who drinks water.

Einstein created this enigma. He claimed that 98% of the worlds population were not capable of solving this problem.

You now have one week to answer this question!