PHIL110 Chapter 1 & 2

An argument with all true premises must be valid.

False

A valid deductive argument can have all true premises and a false conclusion.

False In a valid argument, the premises necessarily lead to the conclusion. If the valid argument had all true premises, it would impossible for that conclusion to be false.

An invalid argument cannot have true premises.

False

One must know if the premises are true in order to determine validity of an argument.

False

An argument with true premises and a true conclusion must be valid.

False I could find an argument with all true yet unrelated premises. Since valid arguments are ones in which the conclusion necessarily follows from the premises, the relationship between the premises and the conclusion is examined before concerning ourselves with the truth of the argument's components. For example: All cats are mammals. All kittens are mammals. Therefore, all kittens are cats. All of these statements are true but the premises don't guarantee that conclusion. Plug in 'dogs' for 'kittens' and see what happens.

Analyze the following deductive argument: Everyone who votes in an election plays a crucial role in a democracy and Jim Bob votes every chance he gets, so he plays a vital role in democracy.

valid with uncertain or arguable soundness For certain? Might some argue that all the components are true? Maybe Jim Bob would argue that it's sound.

If an argument is invalid, then it cannot be sound.

True 'Soundness' is a term reserved for valid argument structures.

A valid argument with all true premises is a sound argument.

True

All sound arguments are valid arguments.

True

Enthymemes: Determine what parts of the syllogism are given (that is, do we find an implicit premise or an implicit conclusion?) Select the missing piece to complete the valid enthymematic syllogism. All elephants are majestic so it follows that Dumbo is majestic.

Dumbo is an elephant.

Enthymemes: Determine what parts of the syllogism are given (that is, do we find an implicit premise or an implicit conclusion?) Select the missing piece to complete the valid enthymematic syllogism. It must be Tuesday--he's wearing his cornflower blue tie.

If he's wearing his cornflower blue tie, it is Tuesday.

Enthymemes: Determine what parts of the syllogism are given (that is, do we find an implicit premise or an implicit conclusion?) Select the missing piece to complete the valid enthymematic syllogism. He would not take the crown. Therefore 'tis certain he was not ambitious. -Shakespeare, Julius Caesar, III,ii, 118. Group of answer choices

If you would not take the crown, you are not ambitious.

Read the following argument excerpt. Select the main conclusion from the choices below. "If it is always impossible not to sin, it is always unjust to punish. Now, it is always impossible not to sin; or, in other words, every sin is necessary. Therefore, it is always unjust to punish." -Gottfried Leibniz, Theodicy: Abridgment of the Argument Reduced to Syllogistic Form

It is always unjust to punish.

Read the following argument excerpt. Select the main conclusion from the choices below. "We see very clearly that neither extension nor shape nor local motion, nor anything of this kind which is attributable to a body, belongs to our nature, but that thought alone belongs to it. So our knowledge of our thought is prior to, and more certain than, our knowledge of any corporeal thing; for we have already perceived it, although we are still in doubt about other things." -Rene Descartes, Principles of Philosophy and Passions of the Soul Group of answer choices

Our knowledge of our thought is prior to, and more certain than, our knowledge of any corporeal thing.

In a valid argument, the premises guarantee the conclusion.

True

Read the following argument. Select the main conclusion from the choices below. Every movie in the theaters now looks worthy of seeing, thus The Rise of Skywalker looks worthy of seeing, since it is in the theaters now.

The Rise of Skywalker looks worthy of seeing.

Enthymemes: Determine what parts of the syllogism are given (that is, do we find an implicit premise or an implicit conclusion?) Select the missing piece to complete the valid enthymematic syllogism. The heater turns on when it's cold outside and it just kicked on.

Therefore, it is cold outside.

A valid argument cannot have all true premises and a false conclusion at the same time.

True

A valid argument form can have a false premise and still be valid.

True

A valid argument is one in which the premises guarantee the conclusion.

True

A valid argument may have false premises.

True

Soundness can be debated after an argument is found to be valid.

True Though the structure of the argument entails the conclusion with certainty, we might disagree about the truth of its components. This is where we'll debate the soundness of the argument.

An invalid argument form might have true premises.

True Truth of the premises doesn't provide enough information about the relationship of the premises to one another. For example, No dogs are mice and no puppies are mice are both true statements but together as premises, they don't guarantee anything for certain about the relationship between dogs and puppies.

Enthymemes: Determine what parts of the syllogism are given (that is, do we find an implicit premise or an implicit conclusion?) Select the missing piece to complete the valid enthymematic syllogism. Either you are with us or against us, so it must be that you are against us.

You are not with us.

Read the following argument. Select the main conclusion from the choices below. If you head south on highway 287, you'll end up in Loveland. Therefore, you should arrive in Loveland, for you took 287 south.

You should arrive in Loveland.