A sound argument must have a true conclusion. TRUE: If an argument is sound, then it is valid and has all true premises. Since it is valid, the argument is such that if all the premises are true, then the conclusion must be true. ... If an invalid argument has all true premises, then the conclusion must be false.

Can a deductive argument have false premises and a true conclusion?

A valid deductive argument cannot have all false premises and a true conclusion. ... A valid deductive argument can have all false premises and a false conclusion. 9. Whether an argument is valid has nothing to do with whether any of it's premises are actually true.

Do premises have to be true to be valid?

It is important to stress that the premises of an argument do not have actually to be true in order for the argument to be valid. An argument is valid if the premises and conclusion are related to each other in the right way so that if the premises were true, then the conclusion would have to be true as well.

What is conclusion as valid and true?

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.

Does the conclusion follow the premise?

The conclusion is the statement that is claimed to follow from the premises. In order to help recognize arguments, we rely on premise indicator words and phrases, and conclusion indicator words and phrases. Inference is the term used by logicians to refer to the reasoning process that is expressed by an argument.

CRITICAL THINKING - Fundamentals: Truth and Validity [HD]

40 related questions found

Can an invalid argument have true premises and true conclusion?

A sound argument must have a true conclusion. TRUE: If an argument is sound, then it is valid and has all true premises. ... If an invalid argument has all true premises, then the conclusion must be false. FALSE: It is possible for an invalid argument to have all true premises and a true conclusion.

What are premises and conclusions?

A premise is a statement in an argument that provides reason or support for the conclusion. There can be one or many premises in a single argument. A conclusion is a statement in an argument that indicates of what the arguer is trying to convince the reader/listener.

What makes a false premise?

A false premise is an incorrect proposition that forms the basis of an argument or syllogism. Since the premise (proposition, or assumption) is not correct, the conclusion drawn may be in error. However, the logical validity of an argument is a function of its internal consistency, not the truth value of its premises.

Are the premises of a cogent argument always true is the conclusion always true?

Yes, the premises of a cogent argument are always true because, by definition, a cogent argument is a strong argument. Strong arguments have probable support to their conclusion. ... The argument form is valid because if the premises are true, then the conclusion must be true and will be valid regardless of the content.

What is an example of a valid argument with a false conclusion?

If Elizabeth Taylor is president of the United States, then Elizabeth Taylor must be younger than 35. Elizabeth Taylor is president of the United States. So, Elizabeth Taylor must be younger than 35. For either example, the logic is valid but the premises are false.

Can the conclusion of an inductively cogent argument be false?

A cogent inductive argument doesn't rule out even this combination—that is, it's possible but unlikely that a cogent inductive argument has true premises and a false conclusion. For instance, if it turns out that Tweety is an ostrich, then the premises are true but the conclusion is false.

What logical conclusion can you draw about an argument that is valid but has a false conclusion?

A valid argument had false premises must have a false conclusion,it is impossible that ones have false premises and a true conclusion. What logical conclusion can you draw about an argument that is valid but has a false conclusion? This argument must have at lease one false premise.

Can a strong inductive argument have false premises?

This argument is inductively strong because if all its premises were true, then it would be highly likely or probable that its conclusion would also true. Inductively strong arguments may have: ... False premises, true conclusion.

Can a valid deductive argument ever have false premises Why or why not p 44?

Can a valid deductive argument ever have false premises? Yes, it can. "The validity or invalidity of an argument is a matter of its form, not its content. The structure of a deductive argument renders it either valid or invalid, and validity is a separate matter from the truth of the argument's statements.

Can a cogent argument have false premises?

Similar to the concept of soundness for deductive arguments, a strong inductive argument with true premises is termed cogent. ... A weak argument cannot be cogent, nor can a strong one with a false premise(s). The concept of true premises sometimes bothers people.

How many premises can an argument have?

Arguments can have any number of premises (even just one) and sub-conclusions. Often arguments have unstated premise(s), that is, premise(s) that need to be added for the premises to support the conclusion. It's always instructive to try to state all the premises necessary to support one's conclusion.

Do cogent arguments always have true premises?

A cogent argument is by definition non-deductive, which means that the premises are intended to establish probable (but not conclusive) support for the conclusion. ... And finally, the premises are actually true.

Can arguments be true or false?

A valid argument can have false premises; and it can have a false conclusion. But if a valid argument has all true premises, then it must have a true conclusion. ... Since a sound argument is valid, it is such that if all the premises are true then the conclusion must be true.

Which conclusion is always true?

When the premisses of a deductive argument are true, the conclusion is always true as well. If a deductive argument is sound, then the conclusion must be true. A deductive argument could have a false premiss and still be sound.

What makes a premise true?

TRUE: If an argument is sound, then it is valid and has all true premises. Since it is valid, the argument is such that if all the premises are true, then the conclusion must be true. So if a valid argument does have a false conclusion, it cannot have all true premises. Thus at least one premise must be false.

What is an argument based on a false premise?

An argument from false premises is a line of reasoning which can lead to wrong results. A false premise is an untrue proposition that forms part of the basis of a logical syllogism. Since the premise (assumption) is not correct, the conclusion drawn may also be wrong.

Is false premise a fallacy?

The fallacy fallacy.

False premises are a feature of informal logical fallacies in particular, which are logical fallacies that occur when there is a flaw in the premises of an argument, which renders the argument logically unsound.

What is the true premises test?

True premises test: The premises in the statement should be true in an argument. Proper form test: The argument should be in good form to be a good argument. ... The premises are true. The first premise is true as Oxygen is essential for life.

What is premises and conclusion with example?

A premise is a proposition upon which an argument is based or from which a conclusion is drawn. ... Merriam-Webster gives this example of a major and minor premise (and conclusion): "All mammals are warmblooded [major premise]; whales are mammals [minor premise]; therefore, whales are warmblooded [conclusion]."

How do you find the premise and conclusion?

If it's being offered as a reason to believe another claim, then it's functioning as a premise. If it's expressing the main point of the argument, what the argument is trying to persuade you to accept, then it's the conclusion.