Following are ten statements. How many of them are true? If any, which ones?

1. Exactly one of these statements is false.
2. Exactly two of these statements are false.
3. Exactly three of these statements are false.
4. Exactly four of these statements are false.
5. Exactly five of these statements are false.
6. Exactly six of these statements are false.
7. Exactly seven of these statements are false.
8. Exactly eight of these statements are false.
9. Exactly nine of these statements are false.
10. Exactly ten of these statements are false.

Self-reference and apparent self-reference

1. Does It Blink?
2. Apparent paradox
3. Set of all subsets
4. An Impossible Page
5. Russell's paradox
6. An Impossible Machine
7. A theorem with an obvious proof

Copyright © 1996-2009 Alexander Bogomolny

1. D.Wells, The Penguin Book of Curious and Interesting Puzzles, Penguin Books, 1992

Self-reference and apparent self-reference

1. Does It Blink?
2. Apparent paradox
3. Set of all subsets
4. An Impossible Page
5. Russell's paradox
6. An Impossible Machine
7. A theorem with an obvious proof

Copyright © 1996-2009 Alexander Bogomolny