HomeenWhat is the fallacy of composition?

What is the fallacy of composition?

The fallacy of composition is an argument that is built from generalizing a particular characteristic of an element to the whole set that integrates that element . It is a fallacy, that is, an argument that seems true but is actually false, since a property or characteristic of an element of a set is not necessarily that of the set, nor is it a class in which it can be classified. that element.

The following statement has the general form of a fallacy of composition:

1. All parts or members of X have the property P. Therefore, X has the property P.

The fallacy of composition

Let’s look at some simple examples of fallacies of composition:

2. Since the atoms in a coin are not visible to the naked eye, the coin is also not visible to the naked eye.

3. Because all the components of a car are light and easy to transport, the car also has to be light and easy to transport.

The parts and the whole

The denial generalization of fallacies is also not correct; in some cases the properties of the components can be extended to the whole. That is, it is possible that arguments similar to the previous ones are not fallacious and are correct even though they do not have logical consistency, as in the following examples:

4. Since the atoms in a coin have mass, then the coin must have mass.

5. Because all components of a car are white, the car must also be white.

non-formal fallacies

Why then are these arguments correct? What is the difference with the two previous arguments? The difference is that the fallacy of composition is a non-formal fallacy, so you have to analyze the content of the argument and not its structure.

A proper characteristic of an element can also be a characteristic of the whole, if that characteristic extended to all the parts of the whole makes the argument valid for the whole. In statement 4, it is correct that the coin has mass because all the atoms that make it up have mass. Similarly, in the fifth statement a car will be white if all its parts are white.

unspoken premises

In these statements there is an implicit argument, a tacit premise that depends on our prior knowledge of the context in which the situation is inscribed. We know that although some parts of a car may be light, when assembling them to obtain the car, the weight of each part is added, and therefore the final weight of the car is going to be much greater than that of any particular part. We have prior knowledge of the car’s assembly process that allows us to conclude that the statement is a fallacy. Similarly, in the example of the coin, we know that matter is made up of atoms and molecules, which are not visible but, grouped together, form macroscopic elements that we can perceive;

When a statement or an argument is made with this structure, it is necessary to inquire about the relationships between the properties of the elements and those of the set that they make up based on the specific statement that is postulated, in such a way that the necessary knowledge can be obtained. to determine if the properties of the set can actually be obtained from the properties of the elements that constitute it.

Some less obvious cases

Let’s look at some examples of fallacies that may be less obvious than the two previously raised:

6. Since each member of a soccer team is the best in the league at each position they occupy on the field, then the team must be the best in the league.

7. Since cars generate less pollution than buses, the pollution generated by cars is less relevant than that of buses.

8. In a free market capitalist economic system, each member of society must act in such a way as to maximize their particular economic interests. This is the way in which society as a whole will achieve the best conditions for its economic development.

formal fallacies and non-formal fallacies

The preceding fallacies help show the difference between formal and non-formal fallacies. The cause that invalidates the claim cannot be identified by analyzing the structure of the argument; on the contrary, it is necessary to analyze the content of the statements and identify the tacit premises. This process is essential to determine if the tacit premises of the statement support it or if it is actually a fallacy.

fallacy of generalization

An important thing to keep in mind is that the fallacy of composition is similar to the fallacy of generalization, but they are actually different. The fallacy of generalization is associated with the impossibility of extending a statement regarding a component of a set to the entire group due to its lack of representativeness of the other members of the group. Conceptually it is different from the fallacy of composition, which is based on properties or attributes that are shared by the members of the group.

Religion and the fallacy of composition

Atheists debate science and religion; The following fallacies may be part of that debate:

9. Since everything in the universe has a cause, then the universe itself must have a cause.

10. It makes more sense that there is an eternal god who always existed than to assume that the universe itself has always existed, because nothing in the universe is eternal. Since no element of the universe is eternal, then it is reasonable to think that the elements that constitute it, that is, the universe itself, is not eternal either.

Aristotle and the Nicomachean Ethics

Determinant philosophers in the history of thought have incurred in the fallacy of composition, as is the case of Aristotle in the Nicomachean Ethics .

11. Is [man] born without a function? Or since his eyes, his hands, his feet, and in general each of the parts that compose him obviously have a function, should it be discerned that man has a function in addition to all of these?

Aristotle argues that simply because the parts, organs and limbs, of a person have a higher function , then the whole, the person, must also have some higher function . But it is not possible to establish an analogy between organs and members of a person and the person himself. Would it also be valid for an animal to establish a higher function given that it has organs that fulfill a certain function?

a higher end

Even if we assume for a moment that it is true that human beings have some higher function , it cannot be concluded that their function is associated with the function of their organs. The term function is used in these statements in a different sense, giving rise to a fallacy of equivocation.


Downden, Bradley. What is a failure?  Internet Encyclopedia of Philosophy, iep.utm.edu/fallacy/. Consulted in May 2021.

Logical fallacies, xtec.cat/~lvallmaj/preso/fal-log2.htm. Consulted in May 2021.

Gambra, Jose Miguel. The place of fallacies in logic. revistas.ucm.es/index.php/RESF/article/viewFile/RESF8788110007A/12292