# Begging the Question (Petitio Principii): Fallacious Circular Reasoning

Begging the question (also called petitio principii or circular reasoning) is a logical fallacy that occurs when an argument’s premise depends on or is equivalent to the argument’s conclusion. In other words, an argument begs the question if one or more of its premises assume that the argument’s conclusion is necessarily true.

For example, the argument “It’s wrong for children to read books with swearwords, so it would be immoral to let children read books that contain swearing” commits the fallacy of begging the question. That’s because its premise (“it’s wrong for children to read books with swearwords”) just rephrases its conclusion (“it would be immoral to let children read books that contain swearing”).

The fallacy of begging the question fallacy an important role in various discussions, so it’s important to understand it. As such, in the following article you will learn more about this fallacy, and see how to respond to it, as well as how you can avoid using it yourself.

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## Terminology of begging the question

The fallacy of begging the question is sometimes referred to using other names, including petitio principiiassuming the conclusion, arguing in a circle, reasoning in a circle, circular reasoning, circular argument, circuius probandi, circulus in demonstrando, and the fallacy of illicit circular argumentation. Distinctions are sometimes drawn between some of these terms and their associated concepts, though they are often used interchangeably in practice.

The term “begging the question” as a name for this fallacy is a translation from the Latin petitio principii, which itself was derived from the Greek names for this fallacy. However, a more accurate translation for this fallacy would be “assuming the conclusion”, which would also describe this fallacy more accurately.

In modern English, “begging the question” is often used with the meaning of “raising the question” or “inviting the question” (i.e., to signify that something prompts the asking of a certain question). For example, this is the meaning that’s conveyed by the statement “you said you like to help people, but this begs the question of when was the last time you did so”. Furthermore, “begging the question” is sometimes also used with the meaning of “to evade a question”, though this is less common.

These alternative uses for the term “begging the question” are sometimes viewed as incorrect. However, in practice they are common, especially compared to the original meaning of this term, which refers to the fallacy. As such, these meanings can be considered additional meanings for the term “begging the question”.

Generally, it’s possible to figure out which meaning of the term “begging the question” someone is referring to based on context. Nevertheless, it’s sometimes better to say “raising the question” or “evading the question” instead of “begging the question”, to avoid misunderstandings or an unnecessary terminological discussion. Similarly, when referring to the associated fallacy, it might be better to use a term like “assuming the conclusion” or “using fallacious circular reasoning”, in order to avoid misunderstandings that stem from people’s lack of familiarity with what “begging the question” means in this context.

## Examples of begging the question

An example of an argument that begs the question is “this company makes the best computers, because no other company makes computers that are as good”, since the premise and conclusion of the argument are functionally equivalent, and are just phrased differently.

In addition, the following is another example of an argument that begs the question, since its premise and conclusion depend on each other in a circular manner:

“This act is illegal because it’s immoral, and it wouldn’t be illegal if it wasn’t immoral in the first place.”

In this short example, the fallacious circular reasoning in the argument is fairly obvious. However, arguments that beg the question can be formulated in ways that make it harder to identify the fallacious reasoning involved, particularly when people use this fallacy in conjunction with other fallacies and rhetorical techniques, like equivocation, circumlocution, red herrings, and appeals to emotions. For example:

“The reason why this act—which really can only be supported by degenerates without a moral compass—is illegal is that it’s entirely immoral and unethical, according to any meaningful set of values, as we’ve seen time and time again in this country, as well as in other eminent countries that share our values. In fact, we can say with absolute certainty that if it wasn’t so completely and utterly despicable and immoral, then there wouldn’t have been a clear need to make it illegal in the first place, which is why those who actually care about things such as propriety and morality have chosen to do so.”

## Explanation of begging the question

Begging the question is considered to be an informal logical fallacy (rather than a formal one), since the logical structure of arguments that beg the question is valid, and the issue is with the premises that they contain, which render the arguments logically unsound. Specifically, one or more of the premises of the argument is either equivalent to the argument’s conclusion or depends on it. As such, to accept this premise you must accept the argument’s conclusion (and vice versa), so the argument cannot establish the truth of a conclusion that is not already known to be true, or to increase one’s confidence in that conclusion.

This logically unsound connection between an argument’s premises and its conclusion means that the fallacy of begging the question is often viewed as a form of circular reasoning. However, there are some objections to this, and an important caveat is that not all circular arguments are necessarily fallacious or commit the fallacy of begging the question.

There’s also uncertainty regarding when it is reasonable to beg the question (or use circular reasoning), and when it is fallacious. For example, if you’re trying to inform someone rather than persuade them, it may be useful to say “coffee will make you feel energized because it’s a stimulant”, even though this argument can be considered to be circular and to beg the question, since a stimulant is often taken to mean a substance that makes people feel energized. As such, a distinction is sometimes drawn between circular reasoning that begs the question and is fallacious (sometimes referred to as vicious circular reasoning), and circular reasoning that is not fallacious (sometimes referred to as non-vicious, virtuous, or benign circular reasoning), though this distinction has been criticized.

Finally, premises and conclusions that are involved in begging the question are not necessarily false, even if the argument that contains them is fallacious as a whole. For example, the argument “it’s raining because it’s raining” begs the question, but both its premise and conclusion, which are identical (“it’s raining”), can be considered true in some situations.

Note: There are many interpretations of this fallacy, and there are many debates on various theoretical aspects of it. However, these are generally not crucial from a practical perspective, and when it comes to understanding the general interpretation of this fallacy.

### Ways of begging the question

There are two main types of circularity that can be involved in begging the question:

• Equivalency circularity, which occurs when a premise of an argument is functionally equivalent to its conclusion. The most basic form of this type of circularity is the argument “P, therefore P”, which is used, for example, in the argument “the sky is blue, therefore the sky is blue”.
• Dependency circularity, which occurs when a premise of an argument depends on its conclusion. The most basic form of this type of circularity is the argument “P is true because Q, Q is true because P”, which is used, for example, in the argument “the sky is blue because it’s not raining, and it’s not raining because the sky is blue”.

These types of circularity can also take other, more complex forms, which can make the associated fallacious reasoning harder to detect. Examples of this are the following:

P is true, therefore P’ is true (where P and P’ are the same statement, just rephrased). For example, “the sky is blue, therefore the sky have a blue color”. This is another form of equivalency circularity.

P is true, therefore not-P is not true. For example, “the sky is blue, therefore it’s false that the sky isn’t blue.” This is another form of equivalency circularity.

P and Q are true, therefore P’ is true. For example, “the sky is blue and high above, therefore the sky have a blue color”. This is another form of equivalency circularity.

A is true because B, B is true because C, C is true because A. For example, “the sky is blue because it’s not raining, it’s not raining because there are no clouds, and there are no clouds because the sky is blue “. This is another form of dependency circularity, where the chain of dependence is extended.

## How to respond to begging the question

When responding to someone who’s begging the question in a fallacious manner, you can use any combination of the following techniques that are appropriate in your particular situation:

• Point out that the problematic premise in their argument is equivalent to or depends on their argument’s conclusion.
• Explain why this type of fallacious reasoning is flawed, potentially by using relevant examples.
• Ask the person who made the argument to explain how the problematic premise is different from the conclusion or stands on its own.
• Ask the person who made the argument to provide separate evidence that their problematic premise is true, without relying on the conclusion of the argument.

Which techniques you should use depends on various factors, such as how the other person begged the question, whether they used this fallacy intentionally or unintentionally, and what you’re trying to achieve by responding to them.

In addition, if the person who used the fallacy also used other fallacies or rhetorical techniques—like red herrings—in conjunction with it, you can address those too. Similarly, if you know that the problematic premise in question is false, you can show that and explain how this affects the conclusion of the argument.

Finally, when responding to arguments that beg the question, keep in mind that the problematic premise and conclusion aren’t necessarily false, even if the argument that contains them is fallacious. And, even if an argument begs the question, it may not necessarily be fallacious, for instance if it’s only meant to inform, rather than persuade (e.g., in the case of the statement “coffee will help you feel energized because it’s a stimulant”).

Overall, to respond to fallacious begging the question, you can point out the problematic relationship between the argument’s premise and its conclusion, explain why this reasoning is flawed, ask how the problematic premise is different from the conclusion or stands on its own, or ask for separate evidence that the problematic premise is true.

## How to avoid begging the question

To avoid fallaciously begging the question yourself, you can do the following:

• Clearly outline your reasoning, by explicitly stating the premises, conclusion, and logical structure of your argument.
• Make sure that your premises aren’t equivalent to your conclusion (i.e., that they are not the same thing stated in different ways).
• Make sure that your premises don’t depend on your conclusion being true.
• Make sure to provide sufficient evidence in support of all of your premises, which does not rely on your conclusions.

In addition, as when responding to someone else who’s begging the question, keep in mind that there are cases where the associated circularity might be reasonable, such as when you mean to inform someone, rather than persuade them (e.g., when saying “coffee will help you feel energized because it’s a stimulant”).

### Origin of the fallacy

The first historical evidence of the fallacy of begging the question is attributed to Aristotle, who discussed it in several works written circa 350 BCE, such as the following:

“People appear to beg their original question in five ways: the first and most obvious being if any one begs the actual point requiring to be shown: this is easily detected when put in so many words; but it is more apt to escape detection in the case of different terms, or a term and an expression, that mean the same thing.

A second way occurs whenever any one begs universally something which he has to demonstrate in a particular case: suppose (e.g.) he were trying to prove that the knowledge of contraries is one and were to claim that the knowledge of opposites in general is one: for then he is generally thought to be begging, along with a number of other things, that which he ought to have shown by itself.

A third way is if any one were to beg in particular cases what he undertakes to show universally: e.g. if he undertook to show that the knowledge of contraries is always one, and begged it of certain pairs of contraries: for he also is generally considered to be begging independently and by itself what, together with a number of other things, he ought to have shown.

Again, a man begs the question if he begs his conclusion piecemeal: supposing e.g. that he had to show that medicine is a science of what leads to health and to disease, and were to claim first the one, then the other;

or, fifthly, if he were to beg the one or the other of a pair of statements that necessarily involve one other; e.g. if he had to show that the diagonal is incommensurable with the side, and were to beg that the side is incommensurable with the diagonal.”

— From “Topics” (Book VIII, Part 13). Aristotle also discusses the concept of begging the question in other works, including “Prior Analytics” (primarily in Book II, Part 16) and “On Sophistical Refutations” (where he mentions it in several areas of the text).

The fallacy was originally described in Greek using the terms “τὸ ἐν ἀρχῇ αἰτεῖσθαι” and “τὸ ἐν ἀρχῇ λαμβάνειν”, which can be translated literally as “asking the original point” or “assuming the original point”, and the fallacy itself was described as “assuming the original conclusion”. In medieval times, this was translated into the Latin petitio principii, and eventually into the English “begging the question”, though “assuming the conclusion” would more accurately capture the original meaning of the term.

### Associated concepts

Begging the question is closely associated with various concepts in logic and rhetoric, including:

• Loaded question (or complex question)- a trick question that presupposes at least one unverified assumption that the person being questioned is likely to disagree with.
• Ignoratio elenchi– a logical fallacy that involves presenting an argument whose conclusion is irrelevant to the discussion, and especially an argument that appears to refute an opposing argument, while actually disproving something else.
• Snuck premise– a controversial and unsupported assumption that someone includes in their argument as if it’s necessarily true.

## Summary and conclusions

• Begging the question is a logical fallacy that occurs when an argument’s premise depends on or is equivalent to the argument’s conclusion.
• For example, the argument “It’s wrong for children to read books with swearwords, so it would be immoral to let children read books that contain swearing” begs the question, because its premise just rephrases its conclusion.
• Even if an argument fallaciously begs the question, its problematic premise and conclusion may be true, and there are cases where circular reasoning can be reasonable.
• To respond to fallacious begging the question, you can point out the problematic relationship between the argument’s premise and its conclusion, explain why this reasoning is flawed, ask how the problematic premise is different from the conclusion or stands on its own, or ask for separate evidence that the problematic premise is true.
• To avoid fallaciously begging the question yourself, you should clearly outline your argument, make sure that its premises aren’t equivalent to its conclusion or depend on it, and provide separate evidence to support its premises.