Various factors influence a person’s beliefs about reality and truth—some of the factors are rational (consistent with reason), some irrational (in conflict with reason), and some nonrational (not based upon reason). Just because a person is not persuaded by a given argument doesn’t necessarily mean that the argument is defective logically. Personal and subjective elements (nonrational factors) can deeply impact the process of persuasion.
It isn’t easy to separate one’s analytical reasoning from emotional and relational issues. At times, nonrational influences can benefit one’s thinking through legitimate assumptions, insightful intuition, or a depth of conceptual vision. Other times, however, nonrational elements can produce negative side effects, such as ignorance, bias, or pride. The personal dimensions of life may stand in the way of a person genuinely understanding and feeling the full force of a powerful argument and, thus, being persuaded by it. A person’s noetic (belief-forming) faculties are seldom as neutral, detached, and coolly objective as many people—especially intellectuals—would like to think. And all people, regardless of educational level, share this subjective, egocentric predicament.
While human beings are uniquely capable of rational thinking it is also true that other powerful factors influence one’s thinking. Therefore, reflective thinkers follow three critical steps when it comes to thinking about thinking. First, they know and seek to follow the ordered principles revealed in the study of logic. Second, they are familiar with the basic ways that reason breaks down into irrationality and they attempt to avoid them. Third, they are aware of both the positive and negative elements reflected in the nonrational elements that impact thinking and they seek to evaluate them with prudence, wisdom, and humility.
Good logical arguments provide reasonable and truthful support (premises) for their central claim (conclusion). And those viable arguments also successfully avoid appeals to intellectual pitfalls like fallacious thinking and other forms of unreasonableness or incoherence.
For more about the healthy intellectual habits provided by the historic Christian worldview, see my book A World of Difference: Putting Christian Truth-Claims to the Worldview Test.