# Western Logic Formal Fallacy Part 2for IAS

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Fallacy

• When an argument fails to support its conclusion, that argument is termed as fallacious in nature.
• A fallacious argument is hence an erroneous argument.
• In other words, any error or mistake in an argument leads to a fallacy.
• So, the definition of fallacy is any argument which although seems correct but has an error committed in its reasoning.
• Hence, a fallacy is an error, a fallacious argument is an argument which has erroneous reasoning.
• In the words of Frege, the analytical philosopher, “it is a logician՚s task to identify the pitfalls in language.” Hence, logicians are concerned with the task of identifying fallacious arguments in logic which are also called as incorrect or invalid arguments.
• There are numerous fallacies but they are classified under two main heads;
• Formal Fallacies
• Informal Fallacies
• Formal Fallacies:
• Formal fallacies are those mistakes or errors which occur in the form of the argument.
• In other words, formal fallacies concern themselves with the form or the structure of the argument.
• Formal fallacies are present when there is a structural error in a deductive argument.
• It is important to note that formal fallacies always occur in a deductive argument.

Complete notes and preparation module at doorsteptutor. com

There are of six types:

## Fallacy of Four Terms

• A valid syllogism must contain three terms, each of which should be used in the same sense throughout, else it is a fallacy of four terms.
• This means, an argument must have only three terms. The three terms are; major term, middle term and minor term.
• Each of these terms should be used in the same sense throughout the argument (premises and conclusion) . For example;
• All dogs are cute
• All cats are animals
• Therefore, all dogs are animals
• Here, the argument has more than three terms; dogs, cute, cats and animals.
• Another name for this fallacy is Quaternio Terminorum.
• In short, when more than three or less than three terms are used in a syllogism then we have a formal fallacy which is called fallacy of four terms.
• Hence, a valid syllogism uses only three terms (not more, not less) .

## The Fallacy of Undistributed Middle Term

• Undistributed middle term is a fallacy when the middle term of the syllogism in not distributed in either of the premises.
• For a valid syllogism, the middle term must be distributed in at least one of the premise.
• It could be either major premise or the minor premise.
• It is also important to note that the Middle term never appears in the conclusion in a valid syllogism.
• For example,
• All people are patriotic
• All Indians are patriotic
• Therefore, all Indians are people
• Here, the middle term, patriotic is neither distributed in the major premise, nor in the minor premise.
• So, although the argument looks valid, it is a fallacious argument.

## The Fallacy of Illicit Process

• When a term distributed in the conclusion is not disturbed in the premises, we have a fallacy of undistributed term or illicit process
• This fallacy is further divided into two parts;
• Illicit Major
• Illicit Minor

### Illicit Major

• When the major term distributed in the conclusion is not distributed in the major premise, we have Illicit major.
• For example, All dogs are mammals , No cats are dogs, Therefore, no cats are mammals
• Here, the major term (mammals) is distributed in the conclusion but it is not distributed in the major premise- All dogs are mammals.

### Illicit Minor

• When the minor term distributed in the conclusion is not distributed in the minor premise, we have Illicit minor fallacy.
• For example,
• All traditionally religious people are old people
• All traditionally religious people are married people
• Therefore, all married people are old people
• Here, the minor term (married people) is distributed in the conclusion but it is not distributed in the minor premise- All traditionally religious people are married people.

## MCQ

1. Formal fallacies are those which

Options:

A. Occur in the form of the argument

B. Occur in the structure of the argument

C. Both A and B

D. Occur in the content of the argument

2. When an argument has less than three terms, it commits the fallacy of

Options:

A. Fallacy of four terms

B. No fallacy is committed

C. Undistributed Middle term

D. None of these

3. When a term distributed in the conclusion is not disturbed in the premises, we have a fallacy of

Options:

A. Illicit Major

B. Illicit Minor

C. Illicit Process

D. Undistributed Middle term

#formal

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#relevance

#Fallacyofillicitprocess

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