Adrian Moore starts his journey through philosophical thought on infinity over the last two and a half thousand years.

For starters, he finds out why the idea made the Greeks so uncomfortable and introduces us to some of the first great thinkers on infinity.

We meet Pythagoras and his followers who divided the world into two fundamental cosmic principles. On one side was everything they thought of as limited or finite, and therefore good, and on the other everything they considered unlimited or infinite, and therefore bad.

The Pythagoreans thought they could explain the world around them in terms of the numbers - 1, 2, 3, 4, etc. - which we use to count finite collections of things, and they were utterly dismayed when they discovered that not every calculation produced the neat answer they expected. According to legend, one of their number was shipwrecked at sea for revealing this discovery to their enemies!

And we meet Zeno of Elea who, after wrestling with the notion of infinity, came to the conclusion that movement itself was impossible.

Producer: Philippa Goodrich

A Juniper production for BBC Radio 4, first broadcast in September 2016.