“Children's playthings are not sports and should be deemed their most serious actions," Montaigne wrote.

Freud regarded play as the means by which the child accomplishes his first great cultural and psychological achievements; through play he expresses himself. This is true, Freud thought, even for an infant whose play consists of nothing more than smiling at his mother, as she smiles at him. He noted how much and how well children express their thoughts and feelings through play.

Why then should we assume that we outgrow the value of play? The wonder of seeing the world through joy, rather than fear. Think about all that you’ve read about the creativity of silicon valley...the atmosphere of fun that entrepreneurs try to create.

Today even education is being built around the idea of projects, of teams, of fun and of wonder.

This is the world that best selling author Steven Johnson explores in Wonderland: How Play Made the Modern World.

My conversation with Steven Johnson: