How do arguments actually work?
Learn how to find what an argument is claiming and whether its reasons really support it.
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Begin with the basics: how arguments work and how evidence helps us decide what to believe.
Before we argue about God or the resurrection, we need one basic habit: know what a claim is trying to prove and whether its reasons actually get us there.
The first question
Jordan is a friend of yours. He knows you are a Christian, but the two of you have never really talked about why you believe it. Lately, you have started taking walks together every so often. Most of the time you talk about work, family, something you saw online, or whatever else comes up.
A few minutes into one of those walks, Jordan says, “Can I ask you something without you turning it into a sermon?” You laugh and tell him to go ahead. “Why do you actually believe Christianity is true?”
A dozen possible answers come to mind, but you tell him that before throwing arguments at him, it probably makes sense to ask what would make an argument good in the first place.
Jordan shrugs. “I guess the reasons have to actually support the conclusion. But people can make almost anything sound convincing if they talk long enough. So how do you tell when an argument actually works?”
A good argument gives reasons that actually support a conclusion. First test the reasoning, then test whether the reasons are true.
A case for Christianity only works if the reasoning underneath it is good. It is easy to hear something that sounds convincing and assume it must be true. We need to know what conclusion is being argued for, what reasons are being used to support it, and whether those reasons actually get us there.
How to evaluate an argument well
In this course, an argument isn't a fight. It's a set of reasons offered in support of a conclusion. The conclusion is what the person is trying to prove, and the premises are the reasons they are giving for believing it.
One way to look at this is to separate two questions. First, does the conclusion actually follow from the premises? That is what validity is asking. Second, are the premises themselves true? When an argument is valid and its premises are true, it is sound.
A valid argument can still reach a false conclusion if one of its premises is false. For example, suppose someone says that all dogs can fly, their Labrador is a dog, therefore their Labrador can fly. The conclusion follows from the premises, but the argument is obviously not sound because the first premise is false. So we cannot only ask whether the reasoning works. We also have to ask whether there is good evidence for the premises.
Not every argument in apologetics will work like a strict deduction. Historical questions often require us to compare several explanations and ask which one best accounts for the evidence. We will do this later with the resurrection. If one explanation accounts for more of the evidence with fewer problems than the alternatives, then we have better reason to accept it.
So simply saying, “Maybe something else happened,” is not enough to answer an argument. A possible alternative is not automatically a good alternative. It still needs evidence, and it needs to explain the facts at least as well as the explanation it is trying to replace.
Bottom line: A good argument needs two things: the conclusion has to follow, and the premises have to be true.
Think about it: Why is “maybe something else happened” not enough to defeat a historical argument?
What makes an argument good?
You tell Jordan that a good argument has two separate jobs: the reasoning has to work, and the important premises have to be true.
You explain validity and soundness, then point out that historical questions often require comparing explanations rather than using a strict deduction.
Jordan laughs. “So somebody can sound really convincing and still be wrong. I suppose I need to pay closer attention to what they're actually saying.”
Use what you learned in a different situation
A coworker says, “Religious people disagree with each other, so no religion can be true.” Identify the conclusion and the main premise that would need to be defended before you answer.
The full course lets you write your response, compare it with a model, and track your progress.
Practice this inside the full courseQuestions this argument still has to face
“Logic is just a Western way of thinking.”
Different cultures may express reasoning differently, but if logic were only a Western preference, you could not argue against it without using logic. A contradiction does not become true because a culture accepts it, and a conclusion still needs to follow from the reasons given.
“Everyone has assumptions, so nobody is objective.”
Everyone does bring assumptions to the table, but that does not mean every assumption is equally reasonable. We can compare them by asking whether they are consistent, whether they fit the evidence, and whether they explain reality better than the alternatives. Having assumptions does not make objectivity impossible.
Use this in a real conversation
- A long argument gets much easier to answer once you slow it down and find the conclusion and the main reasons supporting it.
- There is no reason to answer five claims at once. Take one premise or one step in the reasoning and deal with that first.
- If an argument fails, say that clearly, but do not act as though the conclusion has automatically been disproved. It may still have better arguments behind it.
Logic tells us whether reasoning works. It does not make a weak premise true, so evidence still matters.
Sources for further study
- Biola | Introduction to Christian Apologetics: Begins with apologetics and worldview, truth, knowledge, and faith before moving to arguments for God.
- Biola Catalog | Logic and Critical Thinking: A formal apologetics course on distinguishing good and bad reasoning in arguments for and against Christianity.
- Impact Apologetics | Why I Still Don’t Have Enough Faith to Be an Atheist: Opens with thinking skills, faith and evidence, truth, and the law of non-contradiction.
- Reasonable Faith | The New Atheism and Five Arguments for God: Explains that good arguments need valid reasoning and premises that are more plausible than their negations.
- Ligonier | Defending Your Faith: Explains the role of logic, causality, and clear reasoning in making a Christian apologetic case.
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