Question 1

Singular propositions have a singular subject.But suppose that a certain singular proposition also has a singular predicate.Is the predicate distributed?

Accepted Answer

If a singular proposition has a singular predicate, it is logically necessary for the predicate to be distributed. This is because the predicate is referring to the entire class of objects or attributes that it encompasses within the proposition, which is the definition of distribution in logic. Therefore, the correct answer is B - yes, the predicate is distributed in this scenario.

Question 2

Can a proposition (as a whole) be distributed?

Accepted Answer

Distribution is a property of terms, not of propositions as a whole. Therefore, no proposition can be distributed.

Question 3

If we assume the modern view of existential import, why is the following syllogism invalid? Some terrorists support an independent Palestinian state. John Smith supports an independent Palestinian state. John Smith is a terrorist.

Accepted Answer

The middle term, "supports an independent Palestinian state," is not distributed in either premise, meaning it does not refer to all members of the category in either statement. This leads to an undistributed middle, making the syllogism invalid because it does not logically prove that John Smith is a terrorist based on the given premises.

Question 4

How many rules of validity are there if we adopt the traditional view of existential import?

Accepted Answer

According to the traditional view of existential import, there are four rules of validity: the rule of quality, the rule of quantity, the rule of distribution, and the rule of existential import itself. These rules are used to determine the validity of syllogistic arguments.

Question 5

If we assume the modern view of existential import, why is the following syllogism invalid? No computer is made of clay. All computers are electronic devices. Some electronic devices are not made of clay.

Accepted Answer

The syllogism has universal premises ("No computer is made of clay" and "All computers are electronic devices") but leads to a particular conclusion ("Some electronic devices are not made of clay"), which is not valid under the modern view of existential import.

Question 6

How many rules of validity are there if we adopt the modern view of existential import?

Accepted Answer

The answer of How many rules of validity are there...

Question 7

Suppose that a syllogism has four terms: uncommunicative people, communicative people, Ruth, and people who make friends easily.Can the rules of validity determine whether or not the syllogism is valid?

Accepted Answer

The syllogism has four terms, but the rules of validity require that syllogisms have only three terms. Therefore, we must use immediate inference to collapse the first two terms into one before applying the rules of validity. In this case, we could collapse "uncommunicative people" and "communicative people" into simply "people." Once we have done this, we can apply the rules of validity to determine whether the syllogism is valid.

Question 8

If we assume the modern view of existential import, why is the syllogism EII-4 invalid?

Accepted Answer

The syllogism EII-4 is invalid because it has a negative premise with an affirmative conclusion, or a negative conclusion with no negative premise.

Question 9

If we assume the modern view of existential import, why is the syllogism AEO-2 invalid?

Accepted Answer

The answer of If we assume the modern view of...

Question 10

If we assume the modern view of existential import, why is the following syllogism invalid? All vertebrates reproduce sexually. All vertebrates are animals. All animals reproduce sexually.

Accepted Answer

The answer of If we assume the modern view of...

Question 11

If we assume the traditional view of existential import, why is the following syllogism invalid? All radioactive isotopes are dangerous to humans. No radioactive isotope is a common gas in the atmosphere. No common gas in the atmosphere is dangerous to humans.

Accepted Answer

The answer of If we assume the traditional view of...

Question 12

If we assume the modern view of existential import, why is the following syllogism invalid? No one who has sung for the Metropolitan Opera has been in Kuala Lumpur. No chiropractor has sung for the Metropolitan Opera. No chiropractor has been in Kuala Lumpur.

Accepted Answer

The syllogism is invalid because it contains two negative premises, which is not allowed in a valid syllogism.

Question 13

If we assume the modern view of existential import, why is the syllogism III-2 invalid?

Accepted Answer

Syllogism III-2 is invalid because it commits the fallacy of undistributed middle. The middle term "animal" is not distributed in either premise, and therefore cannot properly relate the two other terms, "dog" and "horse", in the conclusion.

Question 14

If we assume the traditional view of existential import, why is the following syllogism invalid? All of my uncles have difficult jobs. All of my uncles are coal miners. All coal miners have difficult jobs.

Accepted Answer

The answer of If we assume the traditional view of...

Question 15

If we assume the traditional view of existential import, why is the following syllogism invalid? No university is an elementary school.
Some educational institutions are not elementary schools.
Some educational institutions are not universities.

Accepted Answer

The answer of If we assume the traditional view of...

Question 16

If we assume the traditional view of existential import, why is the following syllogism invalid? All premeditated crimes are serious crimes. Some serious crimes are not murders. Some murders are not premeditated crimes.

Accepted Answer

The middle term, "serious crimes," is not distributed in either premise, meaning it does not refer to all serious crimes in either statement, which makes it impossible to draw a valid conclusion about the relationship between the other two terms (premeditated crimes and murders).

Question 17

If we assume the modern view of existential import, why is the syllogism AAA-3 invalid?

Accepted Answer

The answer of If we assume the modern view of...

Question 18

If we assume the modern view of existential import, why is the syllogism EOO-2 invalid?

Accepted Answer

The syllogism EOO-2 is invalid because it contains two negative premises, which violates the rule that a valid syllogism cannot have two negative premises.

Question 19

If we assume the traditional view of existential import, why is the following syllogism invalid? All millionaires are well-paid people. All well-paid people are good at their jobs. Some people who are good at their jobs are not millionaires.

Accepted Answer

The answer of If we assume the traditional view of...

Question 20

If we assume the modern view of existential import, why is the following syllogism invalid? All finger paints are paints. No finger paint is a condiment. All condiments are paints.

Accepted Answer

The answer of If we assume the modern view of...

Quiz 7: Categorical Syllogisms

Singular propositions have a singular subject.But suppose that a certain singular proposition also has a singular predicate.Is the predicate distributed?

Can a proposition (as a whole) be distributed?

If we assume the modern view of existential import, why is the following syllogism invalid? Some terrorists support an independent Palestinian state. John Smith supports an independent Palestinian state. John Smith is a terrorist.

How many rules of validity are there if we adopt the traditional view of existential import?

If we assume the modern view of existential import, why is the following syllogism invalid? No computer is made of clay. All computers are electronic devices. Some electronic devices are not made of clay.

How many rules of validity are there if we adopt the modern view of existential import?

Suppose that a syllogism has four terms: uncommunicative people, communicative people, Ruth, and people who make friends easily.Can the rules of validity determine whether or not the syllogism is valid?

If we assume the modern view of existential import, why is the syllogism EII-4 invalid?

If we assume the modern view of existential import, why is the syllogism AEO-2 invalid?

If we assume the modern view of existential import, why is the following syllogism invalid? All vertebrates reproduce sexually. All vertebrates are animals. All animals reproduce sexually.

If we assume the traditional view of existential import, why is the following syllogism invalid? All radioactive isotopes are dangerous to humans. No radioactive isotope is a common gas in the atmosphere. No common gas in the atmosphere is dangerous to humans.

If we assume the modern view of existential import, why is the following syllogism invalid? No one who has sung for the Metropolitan Opera has been in Kuala Lumpur. No chiropractor has sung for the Metropolitan Opera. No chiropractor has been in Kuala Lumpur.

If we assume the modern view of existential import, why is the syllogism III-2 invalid?

If we assume the traditional view of existential import, why is the following syllogism invalid? All of my uncles have difficult jobs. All of my uncles are coal miners. All coal miners have difficult jobs.

If we assume the traditional view of existential import, why is the following syllogism invalid? No university is an elementary school. Some educational institutions are not elementary schools. Some educational institutions are not universities.

If we assume the traditional view of existential import, why is the following syllogism invalid? All premeditated crimes are serious crimes. Some serious crimes are not murders. Some murders are not premeditated crimes.

If we assume the modern view of existential import, why is the syllogism AAA-3 invalid?

If we assume the modern view of existential import, why is the syllogism EOO-2 invalid?

If we assume the traditional view of existential import, why is the following syllogism invalid? All millionaires are well-paid people. All well-paid people are good at their jobs. Some people who are good at their jobs are not millionaires.

If we assume the modern view of existential import, why is the following syllogism invalid? All finger paints are paints. No finger paint is a condiment. All condiments are paints.