Norman Geisler, along with Ronald Brooks, shows how Christians can greatly improve their thinking skills. "To learn the rules of clear and correct thinking," the authors maintain, "is more than an academic exercise. For the Christian, it is also a means of spiritual service" since "the principles of good reason flow from God's very nature."
After defining logic and delineating its value, the authors focus on two types of reasoning: deductive and inductive. They articulate rules to form syllogisms and list formal and informal fallacies to be avoided. They then outline a strategy for converting everyday reading into logical arrangements and conclude with a discussion on the scientific method of inductive reasoning. Numerous charts and diagrams illustrate the authors' principles, and a glossary explains the technical terminology.