Question

Which of the options below is the missing premise needed to complete this example of modus tollens?

If the drugs are necessary then the patient will improve.
Therefore, the druss were not necessary.
a.The patient will improve.
b.The patient did not improve.
c.The drugs are not necessary.
d.The drugs are necessary

Answer 1

To complete the modus tollens argument, the missing premise is that 'The patient did not improve.' This statement is required for the conclusion that 'the drugs were not necessary' to follow logically.

Step-by-step explanation:

The logical structure being discussed here is modus tollens, which is a valid form of argument in formal logic. The structure of modus tollens is as follows:

1. If P, then Q.
2. Not Q.
3. Therefore, not P.

Given the statement, "If the drugs are necessary then the patient will improve," we can label 'the drugs are necessary' as P, and 'the patient will improve' as Q. To complete the modus tollens structure, we need a premise that states the negation of Q. In this case, the second premise should be "The patient did not improve," which is option b. Thus, we can conclude that the drugs were not necessary.