Chapter 4 argues against the contention that definitive grounds for a system of morality can be found even if God does not exist. Philosopher David Hume pointed out in the 18th Century that you cannot draw a moral conclusion (an “ought”) from factual statements about what is. To do so is to commit a logical fallacy, a category error.
Theists like Dostoievski (“If God does not exist, then everything is permissible”) know that Hume was right, and many atheists like Jean Paul Sartre and Jacques Monod have resigned themselves to the truth of what Hume said. However, that has not stopped other atheists from trying to find some sleight that will evade the force of Hume’s original insight. Even Hume himself tried!
Lennox therefore addresses arguments that have been put forward by Sam Harris, Richard Dawkins, and Michael Ruse and E.O. Wilson and others, and shows that in each case their arguments depend on an unacknowledged non-scientific premise and/or a contradiction of other propositions they have also asserted.
Lennox is able to conclude rightly that “the invective of the New Atheists against the morality of the Bible is invalid, since their atheism gives them no intellectual base for moral evaluation of any sort.” (p. 117).