Mere Christianity | Study Guide

C.S. Lewis

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Mere Christianity | Book 2, Chapter 2 : What Christians Believe (The Invasion) | Summary



Having concluded atheism is "too simple," C.S. Lewis goes on to condemn what he calls "Christianity-and-water." This is a soft version that ignores the problem of evil and the necessity of redemption. These simplistic "boys' philosophies" are not real. Reality, Lewis claims, is complicated, strange, and unexpected. That Christianity shares this quality of strangeness adds to its credibility for Lewis, who states, "It is a religion you could not have guessed."

We are now left to grapple with an enormous problem. The universe is "obviously bad and apparently meaningless," yet we are part of this universe and can recognize evil and meaningless. Besides Christianity, there is one other paradigm that addresses this problem. Dualism, like Christianity, recognizes the universe exists in a state of conflict. Dualism thinks it is a war between separate powers of good and evil, while Christianity recognizes the war as a "civil war, a rebellion" and the world as "enemy-occupied territory."

Dualism's fundamental flaw is revealed when one considers what it means to have a "Good Power" and a "Bad Power." If both powers think themselves good, we must consider how to determine which one is the truly good power. Is the good power the one humans prefer, or is one of the powers mistaken in thinking itself good when it is truly bad?

Lewis points out that good is what we "ought to prefer," not what we do prefer. So our preference is not a criterion for identifying which is the good power. Therefore, one of the powers must be good according to a real standard. This standard, which judges both powers, cannot be either of them and must be "the real ultimate God." The good power, therefore, is the power that "is in a right relation" to this God.

Another problem with dualism is the very existence of a "Bad Power," which supposedly prefers evil to good. Lewis states it is impossible to choose evil directly because all evil is only a misguided attempt to achieve something good. He explains how evil has no existence of its own: "Goodness is, so to speak, itself; badness is only spoiled goodness." Bad is a subordinate property of good, not an independent force. This explains the Christian characterization "that the devil is a fallen angel." Both good and evil arise out of the quest for the good. Therefore, dualism could not be true.


Unlike pantheism, which dismisses the problem of evil by claiming good and evil are merely ideas humans project onto creation, dualism makes a serious attempt to account for the existence of evil. Like Christianity, it takes the problem of evil as its starting point. Lewis calls dualism "the manliest and most sensible creed on the market" next to Christianity. He respects dualism because it takes seriously the same problem Lewis wrestled with throughout his youth. After his mother's death when he was 10, Lewis's world changed forever. He came to believe despair was the natural state of humans. The young Lewis felt the world was unjust and evil and there was nothing to be done about it. He rejected the idea of God as incompatible with what he felt to be true.

Lewis's experience is by no means unique. It's difficult to shrug off the problem of evil because it is so clearly evident there is much in the world that ought to be different than it is. The problem of evil is what is at the root of common existential questions: Why do bad things happen to good people? Why do the innocent suffer while the corrupt flourish? Why is there so much war, pain, and suffering in the world? Humans are perpetually troubled by these observations because of our fundamental need for justice, instilled in us through God's Moral Law. To reduce good and evil to mere human fancy is to accept troubling implications. For example, what imperative is there to help someone who is suffering if evil is divine and is not something that ought to be different? Lewis calls this pantheist idea childish because of its refusal to face what is as obvious as it is disturbing.

Lewis uses Satan, the "fallen angel," to explain the nature of evil. God created Satan as a good creature, but Satan chose to turn away from God and try to claim God's power for his own. In this way Lewis reintroduces the devil—rejected by many modern Christians as an absurd and useless conception—as a symbolic way of understanding how evil does not have its own existence but is merely a perversion of good. Lewis knows his audience is more likely to accept Satan as a symbol of evil than as a horned, hoofed being. He further connects with his audience by emphasizing the metaphor of the universe at war and the world as enemy-occupied territory. Lewis's audience was viscerally familiar with war. They lived with war during 1940 and 1941, as Hitler attempted to crush Britain by a relentless bombing campaign against civilians.

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