Copyright © 1997, Norman Swartz
Department of Philosophy
Simon Fraser University

Answers to the
Second Set of Practice Exercises
on Necessary Conditions and Sufficient Conditions

  1. LSC

  2. LNC

  3. LSC

  4. LNC & LSC

  5. X (Alice may have a brother-in-law, not because she has a sister who is married, but because her husband's sister is married.)

  6. LSC

  7. X

  8. LSC

  9. LNC

  10. LNC

  11. LNC & LSC

  12. X

  13. X

  14. LSC

  15. LNC
  1. LNC & LSC

  2. LNC & LSC

  3. X

  4. LNC

  5. LNC

  6. X

  7. X

  8. LSC

  9. X

  10. LSC

  11. X (Statement 26(a) does not tell us whether there is any other fruit in Sue's basket. Perhaps there are also four grapefruits in Sue's basket.)

  12. X (Statement 27(a) says merely that there are two apples and two oranges in Sue's basket. It doesn't tell us that the fruit belongs to Sue. Perhaps someone has borrowed Sue's basket, and the fruit in the basket belongs to the borrower.)

Return/transfer to Norman Swartz's Philosophical Notes

Return/transfer to Norman Swartz's Home Page