Fallacy of Composition: What It Is, Examples and Difference Between Fallacy of Composition and Division

The compositional fallacy it consists in applying or assuming as valid that the individual characteristics of one or all the members of a group represent the characteristics of the whole group. That is, tends to compose the group without taking into account the individual differences that distinguish them in many ways.

An example of fallacy of composition is to infer that all the dogs of the town are aggressive and bite the passers-by, just because the dog of my house is it. This fallacy is the complete opposite of the fallacy of division, which commits the opposite error. In it the characteristics of the group are taken and applied to each member, without making the distinction.

Composition fallacy

Both fallacies (composition and division) erroneously relate the members of the group as a whole or a whole, ignoring their differences. In the fallacy of the composition the individual assumes something as truth only because it is partly true.

In the division fallacy one or more characteristics of a group are attributed to each of the individuals that comprise it. For example, Jaime's baseball team is the best in the state league for two reasons: he was undefeated last season and won the youth baseball league award. That means that the team's pitcher is the best in the league.


  • 1 What is the compositional fallacy?
    • 1.1 A truth for all
  • 2 Difference between the fallacies of composition and division
  • 3 Examples of composition fallacy
    • 3.1 Example 1
    • 3.2 Example 2
    • 3.3 Example 3
    • 3.4 Example 4
  • 4 References

What is the compositional fallacy?

Logical fallacies are faults of reasoning that are committed due to false beliefs or misleading or wrong arguments. They are a kind of tricks of thought designed to manipulate people consciously or unconsciously.

Fallacies of composition belong to the category of logical, non-formal or informal fallacies. In addition, this type of fallacies is part of the subgroup of ambiguity, as well as the fallacies of accent, mistake and man of straw, among others.

A truth for all

They are called fallacies of composition because"put everything in one bag". They consist in making believe that what is valid or true for a part can be for a whole group or the whole.

For example, under this type of erroneous reasoning the problems of the national economy are extrapolated to the economic problems of a particular family. Beyond having influence, this type of inference can not be made. The debt of a country is not equal to the family debt, nor is the national economy the family economy.

The fact that a country is going through a crisis does not mean that all citizens of that country are doing badly. The crisis of some can become a blessing for others, because they assume the crisis as an opportunity to grow, buy cheap, among other practices.

To explain this fallacy can be cited the case of the behavior of the public in a rock concert. For example, if someone decides to get up to see better, that does not mean that all the time they can see well, or that if everyone gets up they will see better too. What may be true for one may not be true for the rest.

Another case of fallacy of composition occurs when it is believed that all strategies work the same for everyone. For example, the baker who manages to increase his sales by introducing a variety of inexpensive and gluten-free bread in his neighborhood.

The strategy of that baker will not necessarily work for all the bakers of the city, because they are not the same consumers, the bread is made with a special recipe or the type of flour that it acquires is unique, among other reasons.

Difference between the fallacies of composition and division

Both the fallacies of the composition and those of division are related because they deal with the relationship that exists between the whole and the members or parts that compose it. That is, establish a relationship between the set and each member.

However, its main difference is that the fallacy of composition takes an individual characteristic and transforms it into a group characteristic, while the division fallacy does the opposite: it extracts a characteristic from the group and erroneously attributes it to each member in a way individual.

In both fallacies, the generalization error is made with respect to individual and group attributes or properties. By generalizing individually or collectively, as with the fallacies of composition and division, people often make gross mistakes in decision-making.

Examples of composition fallacy

Example 1

"Every brick in that house weighs less than a kilogram. Therefore, the house weighs less than one kilo."

The weight is obviously cumulative, not individual.

Example 2

"If hydrogen is not wet and oxygen is not, water (H2O) is not wet."

The characteristic or property that water takes in liquid state is achieved by joining the hydrogen and oxygen molecules.

Example 3

"So that society can save more money, it must spend less, because I spend less money and I can save more."

This economic paradox can not be applied to the letter. If society as a whole spends less, the consumption or demand of goods and services decreases accordingly. Instead of benefiting the economy, this stagnates and generates a crisis.

Example 4

"The X soccer team has 1 professional player and has won several tournaments. It means that the X football team is inderrotable."

It does not have to be necessarily true, because the fact of having a good player does not assure you that you will never be defeated by another team, even a lower one.


  1. Fallacies of composition and division (and why they matter). Retrieved on March 10, 2018 from americanvision.org
  2. Composition Viewed from iep.utm.edu
  3. Fallacies. Stanford Encyclopedia of Philosophy. Consulted from plato.stanford.edu
  4. Fallacies. Consulted by writingcenter.unc.edu
  5. The Fallacy of Composition in Economics: Definition & Examples. Consulted by study.com
  6. Types of Logical Fallacies. Consulted of examples.yourdictionary.com