Moralistic fallacy

“Effort should be rewarded”

A manager is choosing who gets the team’s quality award. “Priya stayed late almost every night this quarter. Hard work deserves recognition, so her projects must have been the strongest.”

“Hard work deserves recognition” is a reasonable value. But whether Priya’s projects were the strongest is a factual question about the projects, and the value doesn’t answer it. Long hours might go with excellent work, or with a project that kept going wrong. The manager has let what should be true (effort and quality going together) stand in for checking whether it is.

“Of course it works”

A volunteer group runs a free weekend tutoring program. Someone suggests comparing students’ grades before and after. The organizer objects: “These kids deserve help, not to be treated as data points. And anyway, of course it works.”

The first sentence is a value, and it may be a fair reason to be careful about how students are measured. The error is the second sentence: the belief that the program works is being held because the program ought to work, and the refusal to look keeps that belief from ever being tested. This is the shape of the fallacy’s original description: ruling out an inquiry on moral grounds fixes what you think you know.

“Lying on an application is wrong”

A hiring manager learns that a university has no record of a degree an applicant listed. “Everyone signs a statement that their application is truthful, and lying on it would be wrong. It must be a records mix-up.”

Assuming applications are honest is a reasonable default, since most are. The fallacy starts when evidence against that default arrives and is waved away because lying would be wrong. That it would be wrong is exactly why it would matter, not a reason to think it didn’t happen. A records mix-up is possible, and the way to find out is to ask the university or the applicant.

It runs the naturalistic fallacy in reverse:

Tomáš Ondráček argues that this bare form is too broad, because it also covers reasonable presumptions and wishful thinking. His narrower form, which he says fits the original description better, adds the feature that makes it harmful: because of a value commitment, inquiry into some factual claims is blocked, and the opposite claims are accepted.

• Davis’s original sense: putting a question off-limits. The name is usually credited to the microbiologist Bernard D. Davis, in a 1978 guest editorial in Nature. An earlier Nature editorial had suggested that some kinds of scientific knowledge might be too dangerous to seek. Davis replied that science “does not create the realities of nature: it only discovers them”, and that “since blocking off an area of inquiry on moral grounds fixes our knowledge in that area, it becomes, in effect, an illogical effort to derive an ‘is’ from an ‘ought.’” He proposed calling this the moralistic fallacy, “since it is the mirror image of what David Hume and G. E. Moore identified as the naturalistic fallacy.”
• The general sense: “ought, therefore is”. Later writers use the name for any case where a claim about what should be is used to settle a claim about what is. Ondráček describes it simply as “deriving what there is from what there should be,” and notes that it is sometimes called the reverse naturalistic fallacy.
• About emotions. The philosophers Justin D’Arms and Daniel Jacobson (2000) use the name for a specific mistake, as Ondráček quotes them: inferring “from the claim that it would be morally objectionable to feel F toward X, that therefore F is not a fitting response to X.” Whether an emotion fits its situation and whether it’s right to feel it are, on their view, separate questions.

An older phrase with other meanings. “Moralistic fallacy” was in use before 1978 for different mistakes. The historian David Hackett Fischer, for example, used it in 1970 for history writing that “selects edifying facts”. Davis presented the term as new, and Ondráček calls him “probably” the first to coin it; what’s new in Davis is the “ought, therefore is” sense this page covers.

Which fallacy is it the mirror of? Davis spoke of Hume and Moore together, and Ondráček notes that other writers have too. But he points out that the reversal really mirrors Hume’s is–ought gap (reasoning from “is” to “ought”), not Moore’s naturalistic fallacy in the strict sense, which was about defining “good”. See Naturalistic fallacy for the difference.

Close relative: the appeal to consequences. An appeal to consequences rejects a claim because believing it, or its being true, would lead to bad results. The moralistic fallacy rejects a claim because it conflicts with what ought to be. The two often travel together (“that can’t be true, it would be unfair, and people would misuse it”), but one appeals to outcomes and the other to norms.

Close relative: wishful thinking. T. Edward Damer’s textbook defines wishful thinking as “assuming that because one wants something to be true, it is or will be true.” The moralistic fallacy has the same shape, with should in place of want. Ondráček goes further and treats wishful thinking as one kind of moralistic fallacy.

Values legitimately shape expectations and decisions. They just can’t settle questions of fact.

• A norm that’s also a reliable regularity. Rules and functions often describe what usually happens. Expecting the kettle to boil water because that’s what it’s supposed to do, or expecting cars on a one-way street to go one way, is a reasonable default. Ondráček calls this presumptive reasoning: it gives weak support for a conclusion and gives way when counter-evidence appears.
• A procedural rule for acting. “Innocent until proven guilty” tells a court how to act when the evidence runs out. It isn’t a finding that the defendant didn’t do it.
• Deciding what to do about a fact. Once a finding is accepted, values rightly decide the response. Davis himself argued that the goal of justice should rest “on grounds of moral conviction, rather than on vulnerable assumptions about questions of fact.”
• Ethical limits on methods. Refusing to run a harmful experiment is a decision about an action, not a claim about what the experiment would find. Davis drew this distinction himself: medical researchers accept limits on dangerous procedures without being forbidden to seek knowledge.
• Hope, stated as hope. “I hope it works” makes no claim that it does.

The test: would you still believe this if it weren’t what ought to be true, and what evidence would change your mind?

The 8:10 bus

“The bus is scheduled to reach my stop at 8:10, and drivers are supposed to keep to the schedule, so if I’m there by 8:05 I should catch it.”

This moves from “supposed to” to a prediction about what will happen, which looks like “ought, so is”. But the schedule works here as a record of what buses usually do, not as a moral claim, and the speaker leaves five minutes’ margin because buses sometimes run early. Ondráček discusses a similar case (not looking both ways on a one-way street) and argues it’s better read as reasoning from a regularity. This is the reliable regularity condition above.

Accepting the finding, then acting on values

A community garden’s volunteer survey finds that the newest members almost always get the least popular jobs, like hauling compost. The coordinator says: “I didn’t expect that, but the numbers are clear. It isn’t fair, so starting next month we’ll rotate the jobs.”

Moral language and a factual finding appear side by side, but the direction is the legitimate one. The coordinator accepts the finding even though it’s unwelcome, and uses the value of fairness only to decide what to do about it. This is the deciding what to do condition above.

People want the world to match their values, and a fact that seems to threaten a value can feel like an attack on the value itself. Rejecting the fact then feels like defending something important. Davis’s reply was that this makes the value hostage to the facts: if a commitment rests on an assumption about how things are, it’s exposed the moment the assumption fails.

It also borrows from reasonable habits. Norms usually are followed, and things usually do what they’re designed to do, so “it’s supposed to” is often good evidence. The fallacy is keeping that presumption after the evidence has turned against it, or refusing to look.

• Separate the two questions. “Is it true?” and “Would it be good if it were?” have different answers and need different kinds of support.
• Ask what would change the belief. If no possible evidence would, the belief is resting on the value, not on the world.
• Show that the value survives. Often the underlying worry is that admitting the fact would undermine a commitment. Pointing out that the commitment doesn’t depend on the fact, as with the garden’s rotation, can make the fact easier to accept.