Solutions to selected
exercises
Solutions to Exercises for Section 1.1
Solutions to
Exercises for Section 1.2
Solutions to Exercises for Section 1.3
Exercises for Section 1.1
2. Not an argument
3. Argument
4. Argument
5. Not an argument
6. Not an argument
7. Argument
8. Argument
10. Not an argument
11. Not an argument
12. Argument
14. Argument
15. Argument
16. Not an argument
17. Not an argument
18. Argument
20. Not an argument
21. Not an argument
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Exercises for Section 1.2
Part I
2. Inductively strong
3. Deductively valid
4. Neither
6. Deductively valid
7. Inductively strong
8. Deductively valid
10. Inductively strong
11. Deductively valid
12. Inductively strong (?)
Part II
14. All dogs are fish.
All fish are mammals.
Therefore, all dogs are mammals.
15. All dogs are bears.
All bears are mammals.
Therefore, all dogs are mammals.
16. All fish are bears.
All bears are mammals.
Therefore, all fish are mammals.
18. All snakes are reptiles.
No reptiles are mammals.
Therefore, all snakes are mammals.
19. All snakes are reptiles.
No reptiles are mammals.
Therefore, Tim is a human being.
20. Suppose that an argument, A, is valid but that its conclusion is false. Since A is a valid argument, it follows that if its premises are true, then its conclusion must also be true (since the truth of a valid argument’s premise(s) guarantees the truth of its conclusion). However, since A’s conclusion is not true, we may conclude that at least one of its premises is false.
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Exercises for Section 1.3
Part I
2. Two statements
3. Not a statement
4. Statement
5. Statement
6. Statement
8. Two statements
9. Statement
10. Statement
11. Statement
12. Statement
14. Statement
15. Statement
16. Statement
18. Not a statement
19. Statement
20. Statement
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Formal Logic
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