Does a sound argument have to be valid?

A sound argument is necessarily valid, but a valid argument need not be sound. The argument form that derives every A is a C from the premises every A is a B and every B is a C, is valid, so every instance of it is a valid argument.

Can a sound argument be invalid quizlet?

By definition, a sound argument has a valid form and true premises. Thus, a sound argument cannot be invalid. A sound argument must have a true conclusion. A sound argument, by definition, has a valid form and true premises.

What is a sound argument?

A sound argument is a valid argument that has true premises. A cogent argument is a strong non-deductive argument that has true premises.

Can a sound argument have unacceptable premises?

FALSE. A sound argument is both valid and has all true premises. Since a sound argument is valid, it is such that if all the premises are true then the conclusion must be true. Since a sound argument also has all true premises, it follows that a sound argument must have a true conclusion.

How can an argument be valid or invalid?

Valid: an argument is valid if and only if it is necessary that if all of the premises are true, then the conclusion is true; if all the premises are true, then the conclusion must be true; it is impossible that all the premises are true and the conclusion is false. If this is possible, the argument is invalid.

Can a sound deductive argument be invalid?

A deductive argument is said to be valid if and only if it takes a form that makes it impossible for the premises to be true and the conclusion nevertheless to be false. Otherwise, a deductive argument is said to be invalid.

Can a valid argument be wrong?

FALSE: A valid argument must have a true conclusion only if all of the premises are true. So it is possible for a valid argument to have a false conclusion as long as at least one premise is false. 2. A sound argument must have a true conclusion.

Is an argument valid or invalid?

Valid: an argument is valid if and only if it is necessary that if all of the premises are true, then the conclusion is true; if all the premises are true, then the conclusion must be true; it is impossible that all the premises are true and the conclusion is false. Invalid: an argument that is not valid.

What is the difference between valid and sound in an argument?

An argument form is valid if and only if whenever the premises are all true, then conclusion is true. An argument is valid if its argument form is valid. An argument is sound if and only if it is valid and all its premises are true.

Can an argument be sound but not valid?

In other words, the conclusion must be true if the premises are true. An argument can be “valid” even if one or more of its premises are false. An argument is “sound” if it is valid and the premises are true. It is possible to have a deductive argument that is logically valid but is not sound.

Can a sound argument have a false conclusion?

In a valid argument, if the premises are true, then the conclusion cannot be false, since by definition it is impossible for a valid argument to have true premises and a false conclusion in the same situation. So given that a sound argument is valid and has true premises, its conclusion must also be true.

Is an invalid argument an unsound argument?

Any invalid argument is unsound, and any argument with an untrue premiss is unsound. It is possible that premiss (1) is true while the conclusion (2) is false. Therefore, this argument is invalid and cannot be sound. A valid argument with a false premiss is also unsound: 1) If pigs can fly, then ducks can talk.