Valid vs sound flashcards

What is a valid argument?

An argument where if the premises are true, the conclusion must be true.

What is a sound argument?

A valid argument with all true premises, leading to a true conclusion.

True or false: All sound arguments are valid.

True, because sound arguments are always valid.

Difference between validity and soundness.

Validity concerns the form, while soundness requires true premises.

Fill in the blank: An argument can be valid but not _____

sound, if it has false premises.

Example of a valid argument.

If it rains, the ground is wet. It is raining. Therefore, the ground is wet.

Can an argument be sound without being valid?

No, a sound argument must be valid.

True or false: All valid arguments are sound.

False, because valid arguments can have false premises.

What does it mean for an argument to be unsound?

It is either invalid or has false premises.

What is the structure of a valid argument?

Premise 1, Premise 2, Conclusion.

Example of an unsound argument.

If it is a dog, it is a cat. It is a dog. Therefore, it is a cat.

True or false: Valid arguments guarantee true conclusions.

False, validity only ensures logical structure.

Fill in the blank: A sound argument's conclusion must be _____

true, since its premises are true.

Comparison: Valid vs Sound.

Valid: logical structure. Sound: valid + true premises.

What is a counterexample?

An example that shows a valid argument can have false premises.

True or false: An argument can be valid and still be false.

True, validity does not guarantee truth.

What does it mean for premises to be true?

They must accurately reflect reality.

Fill in the blank: If a conclusion follows logically, the argument is _____

valid, regardless of premise truth.

Example of a sound argument.

All humans are mortal. Socrates is human. Therefore, Socrates is mortal.