Rules of Syllogism

Rules of Syllogism

A Formative Assessment

​Rule 1

There should only be three terms in the syllogism​, namely: major term, minor term, and middle term.

Multiple Choice

Based on Rule 1, evaluate the validity of the syllogism below.

All sweets have sugar content.

Sophia is sweet.

Therefore, Sophia has sugar content.

• Valid

• Invalid

​Rule 2

​

The major and the minor terms should only be universal in the conclusion if they are universal in the premises.

Multiple Choice

Based on Rule 2, evaluate the validity of the syllogism below.

No MAVean is lazy.

Samuel is a MAVean.

Therefore, Samuel is not lazy.

• Valid

• Invalid

​Rule 3

​

The middle term must be universal at least once.

Multiple Choice

Based on Rule 3, evaluate the validity of the syllogism below.

Some songs are poems.

MAV Hymn is a song.

Therefore, MAV Hymn is a poem.

• Valid

• Invalid

​Rule 4

​

If the premises are affirmative, then the conclusion must be affirmative.

Multiple Choice

Based on Rule 4, evaluate the validity of the syllogism below.

All human beings have dignity.

The corrupt politician is a human being.

Therefore, the corrupt politician has no dignity.

• Valid

• Invalid

​Rule 5

​

If one premise is affirmative and the other is negative, then the conclusion must be negative.

Multiple Choice

Based on Rule 5, evaluate the validity of the syllogism below.

No human is perfect.

Athena is human.

Therefore, Athena is imperfect.

• Valid

• Invalid

​Rule 6

​

The argument is invalid whenever the premises are both negative.

Multiple Choice

Based on Rule 6, evaluate the validity of the syllogism below.

Some humans are not loving.

Gringo is not human.

Therefore, Gringo is loving.

• Valid

• Invalid

​Rule 7

​

One premise at least must be universal.

Multiple Choice

Based on Rule 7, evaluate the validity of the syllogism below.

Some fruits are not edible.

Pineapple is a fruit.

Therefore, pineapple is edible.

• Valid

• Invalid

​Rule 8

​If one premise is particular, then the conclusion must be particular.

Multiple Choice

Based on Rule 8, evaluate the validity of the syllogism below.

No human can survive alone.

Kevin is a human.

Therefore, Kevin cannot survive alone.

• Valid

• Invalid