• # Practice Syllogism Questions and Answers

Syllogism is an important topic for the section of the paper testing a candidate’s reasoning ability. A Syllogism is a form of reasoning conceptualised by Aristotle wherein you arrive at a specific conclusion by examining two other premises or ideas. In essence, a syllogism is a type of deductive reasoning where the answer is derived by deducting improbable options to arrive at the correct answer. Syllogism derives its name from the Greek word syllogismos, which means deduction or inference.

All syllogistic arguments have 3 parts.

• First is the major premise that offers a generic enveloping statement.
• Second, the minor premise is an idea related to the major premise.
• Lastly, the conclusion is the result we arrive at after analysing the major and minor premises individually and with each other.

Syllogistic statements/arguments are generally provided in a three-line format, as depicted below:

All cats are wearing a bell

Lily is a cat

Therefore, Lily is wearing a bell.

Categorical Syllogism

Categorical syllogisms follow a rule wherein "if A is party to C, then B is party to C”. As we can see, the first example with cats falls under this category.

Let's look at another example of a categorical syllogism.

All horses have 4 legs. I have a horse. My horse has 4 legs.

Major Premise: All horses have legs

Minor Premise: I have a horse.

Conclusion: My horse has 4 legs.

Conditional Syllogism

Conditional syllogisms follow an "If idea A is true, then idea B is true is true as well" logic. These conditional syllogisms may also be referred to as hypothetical syllogisms. This is because the arguments presented aren't always valid. They are simply accepted because idea B has a direct relation with the idea and is therefore assumed to be true.

Study the following examples:

If Rahul likes biscuits, he will like Oreos.

Major premise: Rahul likes biscuits

Minor premise: Oreos are biscuits

Conclusion: Rahul will like Oreos.

Rahul may or may not like Oreos. But since it is mentioned that Rahul likes biscuits it can be assumed that Rahul likes Oreos as well.

If Sakina likes to travel, she must want to visit Morocco.

Major premise: Sakina likes to travel.

Minor premise: Sakina will like to travel anywhere.

Conclusion: Sakina will travel to Morocco.

Disjunctive Syllogism

Disjunctive syllogisms follow an “either A or B is true, if it's A, B is false" format. It contains only 2 premises and the possibility of both statements A and B being correct is mutually exclusive. The statements themselves do not explicitly say if either statement is correct or not. But it's understood that one of them is correct.

The ink is either blue or black

The ink is not blue

The ink is black

Syllogistic Fallacy

Some syllogisms may contain false assumptions that are not based on facts. Here, the major premise is assumed to be true from which the other two premises are drawn. Hence, we run the risk of making false assumptions.

All Dell laptops are black.

My laptop is black.

Therefore, mine is a Dell laptop.

Major Premise: All Dell laptops are black.

Minor Premise: My laptop is black.

Conclusion: My laptop is also a Dell laptop.

All German people can sing beautifully. My neighbour is German. Therefore, he must sing beautifully.

Major Premise: All Germans sing beautifully.

Minor Premise: My neighbour is German.

Conclusion: My neighbour sings beautifully.

Enthymemes

Another type of syllogism which is infrequently tested is an enthymeme. It uses rhetorical arguments and persuasion to make an argument. This is why it is also called a rhetorical syllogism. Here, the minor premise is generally omitted assuming that the audience is also convinced of the same.

Her dress must be so expensive, I know the designer.

Major Premise: Her dress must be expensive.

Minor Premise: I know the designer.

Her new purse can't be ugly. It's a Louis Vuitton.

Major Premise: Her new accessory can't be ugly.

Minor Premise: It's made by famous designer Louis Vuitton.

In an enthymeme, one premise remains implied. In the examples above, we see that the notion of familiarity with someone or something implies an understanding of them and thereby swaying opinion about the same.

Rules of Syllogism

Syllogisms follow 6 basic rules. However, these rules mainly apply to categorical syllogism, as it is the only king of syllogism that mandatorily requires three components as shown above. Let us understand these 6 rules given below to ensure that the candidate devises an error-free argument.

• There must be three components, i.e., the major premise, the minor premise, and the conclusion.
• The minor premise must share its idea with at least one other premise.
• Any terms shared in the conclusion must be shared in either the major or minor premise.
• If either premise is negative, the conclusion is also negative.
• Do not use two negative premises.
• No conclusion can be drawn from two universal premises.

Venn Diagrams:

Named after its designer, John Venn, Venn Diagrams have illustrated circles that intersect at one common point. For syllogisms, these Venn diagrams help us to confirm the accuracy of the statements presented. These diagrams help us especially when complex syllogisms need to be solved. Let us illustrate with a simple example.

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