No True Scotsman (NTS) is a logical error committed when someone tries to change the definition of a word in order to ignore a valid counter-example. The name of this fallacy comes from the cliché most often used to illustrate the mistake. In this story, a man says, “No Scotsman puts sugar on his porridge.” Another man responds, saying, “I was born and raised in Scotland, and I put sugar on my porridge.” The first man replies, “Well, no true Scotsman puts sugar on his porridge.”
Specifically, the No True Scotsman error is an attempt to defend some universal claim—“all X are Y”—by “excusing away” a legitimate instance of the contrary—“here is an X that is not Y.” This deflection involves adding a new requirement, one never legitimately part of the original definition and usually aimed directly at that particular example. NTS is a specific example of an ad hoc (“to this”) fallacy. Determining if something is NTS requires carefully defining the terms and examining whether or not they’re being used consistently by all sides of the discussion.
As the No True Scotsman fallacy applies to biblical Christianity, there is one point on which believers are routinely (falsely) accused of the NTS error. This makes for a useful example to understand what NTS is and is not. The claim in question deals with eternal security; specifically, the common Christian belief that a person who totally abandons faith in Christ was never really saved to begin with. To some, this sounds like a No Tue Scotsman error. At first shake, it seems like one is saying, “Well, no true Christian would do that,” in the same sense as the men discussing sugar and porridge.
These scenarios are not, in fact, the same. In the case of faith in Christ, the Bible says that a person who is saved cannot lose that salvation (John 10:28–29; Romans 8:38–39). The Bible also says that salvation will result in a changed life (2 Corinthians 3:18; Galatians 5:22–23). Those who persist in a godless life were never saved in the first place (1 John 2:4–6; James 2:17–19), and neither were those who appear to “turn away” from the faith (1 John 2:19). In other words, the concept of “not turning away” is part of the biblical definition of being saved.
Defining the phrase turns away is important, as well. In this case, we’re using it to describe the actions of a person who totally abandons the faith, denounces Christ, declares himself a non-believer, etc. Being saved does not imply sinlessness (1 John 1:8–10; 2:1). A believer can still experience doubt, discouragement, or even anger at God (Galatians 6:1). And a believer can act in very non-Christian ways at times (Mark 14:66–72). But the biblical definition of salvation demands a permanent change of heart and mind, which precludes the kind of “turning away” mentioned above.
The Christian stance on those who abandon all connection to their faith, then, is not a No True Scotsman error; rather, it’s an example of correctly using the definition of the word saved and not allowing it to be abused.
Another example that can help show the boundaries of the No True Scotsman fallacy is to imagine a box labeled “waterproof.” If that box is thrown into a swimming pool, and the box fills with water and sinks over the course of several hours, we are justified in saying, “It was never truly waterproof in the first place,” or “A truly waterproof box would never fill with water.” We would not be justified in saying, “Well, waterproof really means that water gets in slowly,” because that changes the definition of waterproof. Pointing out where observations don’t match the original description is not a No True Scotsman fallacy, as long as there is an actual, inherent conflict.
Conversely, if the box sank to the bottom of the pool right away, but never let water in, it would be a No True Scotsman fallacy to say, “Well, a truly waterproof box won’t sink,” because, again, that’s not what it means to be “waterproof.” “Waterproof” and “floats” are two different things.
Where this particular claim becomes interesting, in terms of discussing religion, is that it’s often applied backwards. The No True Scotsman fallacy is an attempt to re-define a word more narrowly than it should be. Critics of religion tend to do the opposite: they re-define words more broadly than they were originally intended. For instance, it is fallacious to blame Christianity for everything done by someone who says the words, “I am a Christian.” Or to contend that a man who never goes to church, lives like the devil, and is generally immoral is “saved,” since he claims he is born again. Given what the Bible says about how salvation changes us, that’s an unreasonable definition of saved.
Accusations of the No True Scotsman fallacy are often levied at Christianity, particularly when it comes to salvation, by those who are actually committing an opposite error. Instead of using a too narrow definition of Christian, they use an ad hoc, overly broad definition, rather than the one that biblical Christianity actually uses.
As believers, we can avoid using the No True Scotsman fallacy by carefully defining our terms, then sticking to them. One is not committing NTS by pointing out a legitimate contradiction between a given example and the definition it’s being used to attack. We are, however, failing according to No True Scotsman when we change a definition specifically to avoid an example. Immediately casting doubt on the salvation of a professed believer caught in sin, for instance, is NTS writ large.
Likewise, it is not an example of the No True Scotsman fallacy to refine a definition when it’s clear that the original term or definition was incomplete or flawed. We simply need to be sure that we’re applying such measures according to truth, not some preferred conclusion. That should apply to both our faith and the beliefs of others.