These bizarre examples attempt to prove one conceptual point or another by deliberately reducing all but one underappreciated feature of some phenomenon to zero, so that what really counts can shine through. The twin earth example sets internal similarity to a maximum (you are whisked off to Twin Earth without being given a chance to register this huge shift) so that external context can be demonstrated to be responsible for whatever our intuition tells us.

He has recently been doing research into clerics who are secretly atheists and how they rationalize their works. In Darwin's Dangerous Idea Dennett writes that evolution can account for the origin of morality. Dennett is an atheist and secularist a member of the Secular Coalition for America advisory board as well as an outspoken supporter of the Brights movement.

Daniel Clement "Dan" Dennett III (born March 28 1942) is an American philosopher writer and cognitive scientist whose research centers on the philosophy of mind philosophy of science and philosophy of biology particularly as those fields relate to evolutionary biology and cognitive science. Fletcher Professor of Philosophy and a University Professor at Tufts University.