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Course 23 · Lesson 5.2

Common fallacies and weak arguments in theological writing

11 minute read

Lessons in this course

Course 23 outline

Module 1: How Research Works

  1. What research is and what a scholarly paper is for
  2. From topic to question: writing a research question that can be answered
  3. The working thesis and how it changes as research develops
  4. Taking notes, recording sources and organizing a project
  5. Academic integrity: quotation, paraphrase and plagiarism

Module 2: Primary and Secondary Sources

  1. Primary and secondary sources in theology and church history
  2. Source criticism: author, date, audience, purpose and transmission
  3. Translations, editions and the problem of reading ancient texts in English
  4. Judging the reliability of a source, including websites and popular books

Module 3: Finding and Reading Scholarship

  1. How peer review works and what it does not guarantee
  2. Finding articles, books and reference works with free and library tools
  3. Reading a scholarly work efficiently and critically
  4. Writing a literature review: summarizing a debate

Module 4: Citation

  1. Chicago notes and bibliography: books, articles and chapters
  2. Citing the Fathers, councils, creeds and online sources
  3. Biblical citation conventions: books, abbreviations, versions and numbering
  4. Managing a bibliography and checking citations

Module 5: Evaluating Arguments and Bias

  1. The anatomy of an argument: claim, evidence, assumption and conclusion
  2. Common fallacies and weak arguments in theological writing
  3. Identifying bias in sources: confessional, ideological and commercial
  4. Confirmation bias in your own work, and ways to reduce it

Module 6: Constructing Arguments and Writing

  1. Building a theological argument from Scripture, tradition and reason
  2. Outlining and drafting a research paper
  3. Clear analytical prose: paragraphs, transitions and plain language
  4. Revising, editing and checking quotations and facts

All courses

Program / Course 23: Research Methodology / Lesson 5.2

What you will learn

  • Define a fallacy and explain why a fallacious argument can still have a true conclusion.
  • Recognize ten common fallacies as they appear in religious and historical writing.
  • Avoid mislabeling a strong argument as a fallacy.
  • Check your own drafts for the same weaknesses.

The big idea

A fallacy is a pattern of reasoning that looks convincing but fails to support its conclusion. Fallacies are common in every field, including theology, partly because the subjects are important and feelings run high. Naming them helps to find what is wrong with a weak argument. Two cautions apply: a conclusion can be true even when the argument for it is bad, and a label should be used to examine an argument, not to dismiss an opponent.

Key terms

Fallacy
A flaw in reasoning that makes an argument less convincing than it appears.
Ad hominem
Attacking the person making a claim instead of the claim. The Latin means ‘to the person’.
Straw man
Misrepresenting an opponent’s view in a weaker form, then refuting that form.
Begging the question
Assuming in the premises what the argument is supposed to prove.
Appeal to authority
Treating a claim as true only because an authority said it, where the authority has no relevant expertise or evidence is needed.
Genetic fallacy
Judging a claim by its origin instead of its merits.
False dilemma
Presenting only two options when more exist.
Post hoc
Assuming that because one event followed another, the first caused the second.
Anachronism
Reading later ideas, words or categories back into an earlier time.

Background

Logicians since Aristotle have catalogued errors of reasoning, and the Stanford Encyclopedia of Philosophy’s article on fallacies, listed in this course’s readings, gives a careful modern account of how they are classified and what the classification can and cannot do. The article also warns that many apparent fallacies are reasonable in some settings. Appealing to an expert is usually sensible, for example, and noting that a witness is biased is sometimes a good reason to check the testimony. The fallacy lies in the misuse, not in the form.

Theological writing has its own temptations. The subject matter is dear to the writer, and the audience is often assumed to share the writer’s convictions. Sermons and devotional works are meant to persuade and encourage, and their rhetoric may not meet the standard of a scholarly paper. Polemical works, from the early church onward, often portrayed opponents harshly. A research paper should hold to a stricter standard than the sermon or the pamphlet, because the reader is invited to test it.

The aim of studying fallacies is partly defensive and partly constructive. Defensively, it helps you spot weak arguments in others. Constructively, it helps you see them in your own drafts, where they are harder to detect. In both cases the proper response to a fallacy is to restate the argument without the flaw and see what remains. Sometimes a good argument is hidden inside a poor one. Sometimes nothing remains.

Step-by-step explanation

Step 1: Learn the attacks on persons and positions

An ad hominem argument dismisses a view because of who holds it: ‘He is a heretic, so his reading of this verse is worthless.’ The reading must be judged on its evidence. The straw man misstates an opponent’s view so that it is easy to refute. Test for it by asking whether the opponent would accept your description of the view.

Note that pointing out a person’s relevant bias or interest is not necessarily ad hominem. It is a reason to check the evidence, not a reason to dismiss it.

Step 2: Learn the circular and authority-based errors

Begging the question assumes the conclusion in the premises: ‘The council was right because it was guided by the Spirit, and it was guided because it reached the right conclusion.’ Among believers, arguments from authority are often legitimate within a tradition, since a tradition may hold that a council or a text is authoritative. The error comes when the authority is invoked as if it were persuasive to someone who does not accept it, or when the question being researched is whether the claim is supported.

An appeal to authority also fails when the authority is outside his field, or when many experts disagree and only one is named. The remedy is to give the evidence and say who holds what.

Step 3: Learn the errors of origin, cause and alternatives

The genetic fallacy says that a view must be false because of where it came from, or true because of its pedigree. A custom with pagan parallels is not thereby false, and an ancient custom is not thereby right. Post hoc reasoning assumes that because B followed A, A caused B. A false dilemma offers two choices when others exist: ‘Either the text is a perfect record or it is worthless.’

Related errors are the slippery slope, which claims without evidence that one step will inevitably lead to extreme results, and hasty generalization, which draws a broad conclusion from a few cases.

Step 4: Watch for errors special to historical and textual work

Anachronism reads later ideas back into earlier writers: assuming that a second century author meant by a word what the sixteenth century debate meant by it. Proof-texting quotes a verse or a sentence without its context to support a claim the whole passage does not support. Cherry-picking selects only the evidence that fits, and the argument from silence treats the absence of a mention as proof of absence, though many things are not mentioned in the surviving sources.

The argument from silence is not always a fallacy. If a topic would certainly have been mentioned had it existed, silence can be evidence. It must be argued, not assumed.

Step 5: Respond fairly to a fallacy

When you find a flaw, say what it is and why it matters, without attacking the writer. Then restate what the argument would need in order to work. If you find that the conclusion might still be true, say so. Finally, check your own drafts for the same errors, and ask a reader to look for them.

Do not use the names of fallacies as weapons. Calling every opposing argument a fallacy is itself a way of avoiding it.

  1. Am I answering the argument or attacking the person?
  2. Would my opponent accept my statement of their view?
  3. Does my premise assume what I am trying to prove?
  4. Am I judging this idea by its merits or only by its origin?
  5. Are there more than two options?
  6. Is this verse quoted in its context?

Examples

Ad hominem

‘Marcion was expelled from the church, so nothing in his list of Pauline letters is worth considering.’ The question of the evidence for his list is not answered by his reputation. A scholar might still treat his testimony with care for other reasons.

Straw man

‘Those who prefer an early date for the Gospel say that nothing could have changed in the tradition.’ An early-date scholar would not say this. Refuting the claim answers nothing. (A constructed example.)

Proof-texting

A speaker quotes a single clause from a letter to show that the author opposed an institution, while the next sentence says the opposite. Reading the full paragraph corrects the claim. (A constructed example.)

Argument from silence

A student says that because a writer of the second century never mentions a practice, it did not exist. The student has not shown that the writer would have mentioned it, or that the surviving sources are complete. The claim is too strong. (A constructed example.)

Different perspectives

Catholic

Catholic tradition values argument and has a long history of logic and disputation. It also teaches that the Church has authority to interpret Scripture and tradition. A Catholic writer may appeal to that authority within the Church, and should recognize that in a scholarly paper the evidence for a historical claim must be shown.

Orthodox

Orthodox writers often appeal to the consensus of the Fathers. This is a form of reasoning from authority that is considered sound within the tradition, and scholars of the tradition also stress that the consensus must be shown from the texts, not assumed. Isolating a single saying from a Father is regarded as a misuse.

Protestant

Protestants have often accused one another and Catholics of proof-texting, and have also been accused of it. Careful Protestant interpreters stress reading texts in their literary and historical contexts. Fee and Stuart’s guide, in the library, warns against taking verses out of context.

Philosophers and historians

Philosophers stress that identifying a fallacy does not show the conclusion is false. Historians add that arguments from silence, from the absence of evidence, can be good or bad depending on what the sources would have been expected to say. Both warn against treating a list of fallacies as a mechanical test.

Why it matters

Weak arguments waste the reader’s time and, worse, may lead to false beliefs about matters of importance. A researcher who knows the usual fallacies writes better and reads better. More than that, fairness to opponents is a moral matter. Misrepresenting someone’s view to defeat it is a form of false witness, and Scripture asks for the opposite.

Common misunderstandings

Misunderstanding: If an argument contains a fallacy, its conclusion is false.

Correction: The conclusion may be true. The fallacy shows only that this argument does not establish it. A better argument may exist.

Misunderstanding: Appealing to authority is always a fallacy.

Correction: Relying on a genuine expert on a point within the expert’s field is reasonable. The fallacy arises when the authority has no relevant knowledge, when authorities disagree, or when the appeal replaces evidence that the situation requires.

Misunderstanding: Fallacies are errors made only by my opponents.

Correction: Everyone commits them, often without noticing. The first place to look is your own draft.

Misunderstanding: Noting a writer’s bias is ad hominem.

Correction: It is ad hominem only if bias is used to dismiss the argument without examination. Noting bias is a reason to check the evidence more carefully.

Knowledge check

What is a straw man, and how can you avoid it?

A straw man misrepresents an opponent’s position in a weaker form and then refutes that form. To avoid it, state the opposing view in terms its holders would accept, quote them where possible, and read their strongest presentation. If an opponent would not recognize your description, revise it.

Why can an argument be fallacious and its conclusion still be true?

A fallacy shows that the reasoning does not establish the conclusion. It does not show the conclusion is false. The conclusion may be supported by other, better arguments. Dismissing a conclusion because one argument for it is poor is itself a mistake in reasoning.

What is proof-texting?

Proof-texting is quoting a verse or sentence without its context to support a claim that the whole passage, or the author’s wider thought, does not support. The remedy is to read the passage in its paragraph, book and setting, and to say what the author was doing in writing it.

When is an argument from silence reasonable?

It is reasonable when a source would almost certainly have mentioned a matter if it had existed, and the source is known to be reasonably complete on that kind of subject. It is weak when the sources are few, fragmentary or on other subjects. The writer must argue that silence is significant instead of assuming it.

Think it through

  1. Which fallacy are you most likely to commit when you feel strongly about a subject?
  2. Have you ever misrepresented a view you disagreed with? How did you discover it?
  3. Why might the same appeal to a council be sound for a believer within a church and weak for a historian?
  4. How could you invite others to point out fallacies in your drafts?

Independent assignment

A fallacy hunt

In your own notebook, find three short arguments about religion or church history from different kinds of sources, such as a sermon, a popular article and a scholarly work. Write about 400 words identifying any weak steps, naming the fallacy if one applies and explaining why. Then reread a page of your own writing and note one place where your reasoning could be stronger. Do not send this to anyone.

Further study