Slide 1 of 7

If a set of WFFs is inconsistent, would the set become consistent by adding more WFFs to it?

  • Yes

  • No

If you have a set containing only tautologies, is the set consistent?

  • No

  • Yes

If A is consistent with B, and B is consistent with C, does it follow that A must be consistent with C?

  • Yes

  • No

If A is inconsistent with B, and B is consistent with C, does it follow that A must be inconsistent with C?

  • No

  • Yes

If X, Y and Z form an inconsistent set of WFFs, then X and Y are inconsistent with each other.

  • No

  • Yes

If X is an inconsistent WFF, and Y is an inconsistent WFF, then X is inconsistent with Y.

  • No

  • Yes

Solution list
Question 1

If a set of WFFs is inconsistent, would the set become consistent by adding more WFFs to it?

No

Question 2

If you have a set containing only tautologies, is the set consistent?

Yes

Question 3

If A is consistent with B, and B is consistent with C, does it follow that A must be consistent with C?

No

Question 4

If A is inconsistent with B, and B is consistent with C, does it follow that A must be inconsistent with C?

No

Question 5

If X, Y and Z form an inconsistent set of WFFs, then X and Y are inconsistent with each other.

No

Question 6

If X is an inconsistent WFF, and Y is an inconsistent WFF, then X is inconsistent with Y.

Yes