True or false: using diagrams to test arguments

Exercise and reference answers

Questions

1. Statement is true

   Yes

   Statement

   A conclusion is valid only if every consistent diagram supports it.

2. Statement is true

   No

   Statement

   One diagram that supports the conclusion is enough to prove it.

3. Statement is true

   Yes

   Statement

   One consistent diagram that contradicts it disproves the argument.

4. Statement is true

   Yes

   Statement

   Diagrams can show that nothing follows from the premises.

5. Statement is true

   No

   Statement

   Diagrams add facts not present in the premises.

Explanation