One of the twentieth century’s greatest defenses of the Christian faith is C.S. Lewis’s Mere Christianity.  The book contains many good and persuasive arguments; I often recommend it, and expect to go on doing so.  And yet the book’s greatest strength, viewed in one way – the minimalism expressed by the adjective mere -- turns out to be identical with its greatest weakness, viewed in another way.

The point of the mere is that Lewis was not trying to defend a particular conception of Christianity, be it Catholic, Evangelical, Presbyterian, or what have you, but just Christianity.  His strategy was to get the reader into the entrance hall; the reader could decide on his own what room to enter from there.

How wonderful to avoid the sectarian quarrels and go straight to the heart of things.  So what is the problem?  The problem is that Lewis was not really doing that.

In fact, he couldn’t have done that, for consider what kind of mere his mere is.  To go to the heart of things, Lewis would have had to identify and defend the beliefs most truly central to the Church founded by Christ.  But to do that would have risked the very quarrels he was trying to avoid, for as he points out, which beliefs are central is one of the things which the different conceptions of Christianity disagree about.  Instead, Lewis said, his aim was to defend only the beliefs about God and man shared by almost all or almost all who have called themselves Christians.

To put it another way, his mere is not the essential mere, but only the statistical mere.

But aren’t these two meres the same thing?  Aren’t the beliefs most truly central to the Church founded by Christ the very same as the beliefs of most people who call themselves Christians?  Hasn’t orthodox Christian faith been defined by St. Vincent of Lerins as “what has been believed everywhere, always, and by all”?

St. Vincent did say that.  But his excellent criterion has no meaning unless we specify who is meant by that “all.”  Who did St. Vincent himself mean by it?  He meant all who cling to the Sacred Tradition of the Catholic Church.  As he explained, “We shall hold to this rule if we follow universality, antiquity, and consent. We shall follow universality if we acknowledge that one Faith to be true which the whole Church throughout the world confesses; antiquity if we in no wise depart from those interpretations which it is clear that our ancestors and fathers proclaimed; consent, if in antiquity itself, we keep following the definitions and opinions of all, or certainly nearly all, Bishops and Doctors alike.”

Unlike St. Vincent’s “all,” which is really a criterion of adherence to Sacred Tradition, Lewis’s statistical “all” opens the door to a zoological garden of beliefs, and every day the zoo grows larger.  Mary Baker Eddy called herself a Christian.  The “God is dead” theologians of the nineteen-sixties called themselves Christians.  Mormons, who think God one of an infinity of gods, call themselves Christians (at least these days they do).  I used to know an Episcopalian chaplain who denied the Resurrection, but recited the Creed “as an act of solidarity with the community."

Some of these species of belief are pretty well populated, so that if mere Christianity means merely what all or almost all who call themselves Christians have believed, there is nothing left of it.

But I suggested that the book is great.  So what saves it?  See the next post for the answer.