## paradox

Here's a resolution for one of probability theory's most famous paradoxes.

**Andrew Stickland**explores the dangers that face the unwary when using a single number to summarise complex data.

**Jon Walthoe**explains the tricks involved and how great thinkers like Pythagoras, Newton and GĂ¶del tackled the problems.

**Eugen Jost**is a Swiss artist whose work is strongly influenced by mathematics. He sent us this Postcard from Italy, telling us about his work and the important roles that nature and numbers play in it.