Back when I was an adolescent, the first big challenge to my faith came from reading the works of B F Skinner. Prompted by a cover story about the Harvard psychologist in Time magazine, I delved into his Walden Two and Beyond Freedom and Dignity. ‘By God’, I remember thinking, ‘there’s no such thing as free will!’ The entire edifice of Christianity seemed to totter and fall.

Skinner thus assumed an enormous importance for me at an impressionable stage of my intellectual development. He became something of an obsession. One night on a whim I called the directory assistance for Cambridge, Massachussetts, and found to my surprise that his phone number was listed. I lost no time