Mere Christianity

Lewis draws on several scientific ideas over the course of Mere Christianity, either in outright support of his claims (as when he notes how modern science has troubled our understanding of linear time), or, more loosely, to provide an analogy for his arguments. In both cases, the effect is to suggest that religion is compatible with modern science and perhaps even to lend it some of science’s credibility in the popular imagination. Whether Lewis’s claims about science stand up to scrutiny is of course debatable, but it is an effective rhetorical strategy, and one of the best examples of it is Lewis’s use of evolution.

The significance of this as a motif lies in the fact that, as Lewis mentions more than once, learning about evolution naturally prompts a lot of people to wonder how human beings will evolve in the future. Strictly speaking, of course, this “next step” wouldn’t necessarily be superior to humans in strength, intelligence, etc. (218)—simply better suited to surviving in some respect—but the fact that this is how people tend to imagine it is useful to Lewis, who argues that in a certain sense the “next step” has already happened. We don’t recognize it, however, because we can only imagine evolving into better versions of what we already are: “People see (or at any rate they think they see) men developing great brains and getting great mastery over nature. And because they think the stream is flowing in that direction, they imagine it will go on flowing in that direction” (219). Lewis, however, argues that in much the same way that the dinosaurs gave way to something radically different—mammals—people too will become something categorically other than what they currently are. By this, he of course means people animated by a spiritual life as well as a biological one:

[T]he Christian view is precisely that the Next Step has already appeared. And it is really new. It is not a change from brainy men to brainier men: it is a change that goes off in a totally different direction—a change from being creatures of God to being sons of God (220).  

Lewis of course uses many analogies throughout Mere Christianity, but one of the more extended metaphors he develops surrounds the idea of humans as tin or toy soldiers: entities that look human but aren’t really alive. Developing the metaphor further, Lewis suggests that if a child could somehow begin transforming their toy soldiers into real human beings, the toys might be resistant: “It would involve turning the tin into flesh. And suppose the tin soldier did not like it. He is not interested in flesh: all he sees is that the tin is being spilt. He thinks you are killing him. He will do everything he can to prevent you” (179). In this way, soldiers function as a symbol for humanity in its fallen state, which is naturally inclined to resist the spiritual life God is offering.

The image of the toy soldiers of course hearkens to Mere Christianity’s broader military motif, but also to a motif involving children’s play and games. Another prominent example is the idea of pretending or playing dress up, which Lewis argues prepares children for adulthood in much the same way that “dressing up as Christ” trains us to be children of God (188). As with the evolution motif, the overall effect is to compare the process of developing a spiritual life to a natural process with which readers are already familiar—in this case, a child’s growth into an adult. It also functions as a reminder of our frailty and dependence on God, whose wisdom and power dwarfs our own in the same way that a parent’s does their infant’s.