EXERCISES FOR PART THREE
I. What is wrong with the following statements?
1.Validity is when an argument is true; i.e., its premises are true and its conclusion is true. Validity has to do with form and nothing to do with being true
2.An argument is valid when it is both sound and true.
An argument is valid when it is sound
3.Premises can be true or false; conclusions are sound or unsound. Premises can be true because they are statements, and conclusions can be true abecause they are also statements. Truth does not apply to arguments as a whole
4.An argument's validity depends on the truth of its premises. Arguments are never true or false. Validity depends on the arguments form.
5.An argument's soundness depends upon its form.
Validity of an argument depdns on its form. A valid argument is valid or invalid its form
II. Determine whether the following statements are true or false, and why.
1.A valid argument can have false premises.
True, an argument can have one or more false premises, argument may still be valid though because if the premises are true the conclusion is also
2.A sound argument can have a false conclusion.
False, soundness depends on form and content
3. If an argument is sound, then it must be valid.
True, Sound argument an argument that is valid
4.All valid arguments are also sound arguments.
False, a sound argument is an argument that is valid with true premises
5.All sound arguments are also valid arguments.
True, a sound argument has to be valid
6. If an argument has all true premises and a true conclusion, then it is sound. False, argument must be valid
7.A valid argument must have a true conclusion.
False, a valid argument does not depend on its conclusion, depends on form
8.It is correct to say that an argument is true or false.
9.An invalid argument must have at least one false premise. False, argument being valid or invalid is based on form, not whether...