In my sophomore college year, I took an English composition course. Our professor began by explaining that we’d spend our first week learning about errors that his writing students tended to make frequently. I was slightly puzzled when among the errors we’d be studying he listed “logical fallacies.”

I was expecting him to drill us on grammatical errors; logic was something I associated with math and philosophy.He went on to explain that a person cannot write persuasively if he or she doesn’t know how to formulate a logical argument.

Anyway, that’s what educated people thought in the late 1970s, but people seem less demanding today. My own impression, based on what I read in the news and elsewhere, is that many Americans are unable to distinguish between a sound argument and a fallacious one. More and more, I observe people who ought to know better readily embracing arguments that are formally fallacious.

In the absence of an ability to recognize what constitutes a sound argument, people tend to choose sides on the basis of personal taste. If someone presents a false argument that leads to a conclusion that I like, ignorance of the rules of logic lets me be content to embrace the conclusion (and perhaps the argument as well). Of course, this affects every topic: politics, theology, science, or anything else.

A decade or so ago I met a sweet little old widow in a Reformed church. Somehow in the course of conversation she volunteered that she was a Theonomist. I was intrigued, having never met a little-old-lady-Theonomist before, so I asked her why she was persuaded of Theonomy. “Because,” she said, “they believe in capital punishment, and I do too.” Dumbfounded, I changed the subject.

In the years since then I’ve observed quite a few people following a similar reasoning process: “I like that argument, so it must be true” or, “I don’t like that one, so it must be false.” These sentiments sometimes constitute the entirety of their “analysis.” It feels as though personal taste is taking over the role of logic for a good many of us – Christians included. If this is true, it would be a great shame, not least of all because it makes us easy prey for demagogues.

I’ve also found myself slipping into similarly lazy habits of thought. So – in an attempt to re-learn some things I’ve forgotten and wage a small battle in defense of sound thinking, I’m planning to write a series of pieces here on logical fallacies. My hope is that doing this will force me to refresh the use of sound logic in my own writing (and thinking) and perhaps help others to do so too. Stay tuned.