This is philosophy bites with me David Edmonds and me Nigel War Burton.

Philosophy bites is available at W.

That's W. W. There was a young man who said God must find it exceedingly odd to think that the

tree should continue to be when there's no one about in the quad.

Dear sir, your astonishment's odd. I'm always about in the quad. the

court, dear sir, your astonishment's odd, I'm always about in the quad, and that's why the tree will continue to be

since observed by yours faithfully God.

This rather succinct summary of the philosophy of George Barclay was penned well after his death.

Barclay, born in Ireland in 1685, rose to become a bishop, but his fame rests on his metaphysics.

He was an idealist believing that reality consists only of minds and ideas, not in objects or things.

According to John Campbell, from the University of California Berkeley,

Berkeley's philosophy must be understood against a background of the

17th century scientific revolution, a revolution whose influence continues to be felt today, which in some ways, says

Professor Campbell, is most unfortunate.

John Campbell, welcome to Philosophy Bites.

It's great to be with you here.

We're going to focus on Barclay's puzzle.

Could you just say what Barclay's puzzle is?

Berkeley was working after the impact of Newton and Galileo, after the impact of the 17th century

scientific revolution in physics. The big impact was that if the

physicists were right, if Newton was right, then the world that we live in was not a bit like the way we think it is. Newtonians were always pointing out that really what the world consisted in was mostly empty space,

occasionally interspersed with lonely clumps of atoms. The world we think we ordinarily encounter, the world of

...