Although a few materialists deny the existence of consciousness, many more would reject Mr Searle's description of their position.

ECONOMIST: Philosophy of consciousness

The topics of conversation included evolutionary theory, libertarian philosophy, and the anthropic principle, which holds that observations about the universe depend on the existence of a consciousness that can observe.

NEWYORKER: No Death, No Taxes

Her three Cs are collective intelligence, collective consciousness and co-existence.

ECONOMIST: Contemporary art

And Endless Forms at the Fitzwilliam Museum, in Cambridge, considers how Darwin's ideas penetrated the consciousness of the great artists of the era, inspiring visual representations of the struggle for existence, of natural attraction and sexual selection, and the origin and descent of man.

BBC: Friday 11 September: Darwin special