Why does an atheist bother to get up in the morning?

That's the question Richard Dawkins seeks to answer as he continues his exploration of the big questions of life in a world shaking off religious faith.

In the face of what appears to be a blindly indifferent universe, Dawkins argues that we each have to forge our own sense of meaning.

He meets the comedian Ricky Gervais, an atheist since the age of seven, for whom meaning comes through doing something creative.

For Dawkins, it is the awe and wonder in scientific enquiry - from the human genome to the quest for the Higgs Boson - that get him up in the morning.