What is the moral argument for the existence of God in Mere Christianity by C.S. Lewis?

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Michael Otis eNotes educator| Certified Educator

C.S. Lewis advances the moral argument for the existense of God in the first part of his seminal book of Christian apologetics, Mere Christianity, but not before defending the reality of the moral law itself. That is, the moral law presupposes a Lawgiver. According to Lewis, the moral law consists of the fundamental rules by which the universe and all who reside in it are bound. Although much energy has been expended in debunking belief in an objective concept of right and wrong, Lewis argues the moment the sceptic opines "It isn't fair" he has defaulted to the authority of a superior moral law. Arguments about moral conduct, namely, that one action is superior to another, take for granted that some kind of higher law exists, one to which appeal can be made the world over. This truth having been established, Lewis moves on to its origin, since, he avers, everything in the universe had to have a beginning. Philosophers advance two theories for this: One is materialist, the other religious. In the former, the principles governing the universe arose by chance. In the latter, since morality throughout the history of the world appears in the form of laws and codes, it stands to reason that it originated in the conscious mind of a transcendent Lawgiver - God.