Chapter Three, Tutorial Three
Logically True, False, and Indeterminate in SL

Back in chapter one, we introduced various logical notions trading on the concept of possibility.

For example, we said that a sentence is logically true if and only if ______?

If and only if what??? Select the correct way to fill in the blank:

  1. the sentence could not possibly be true.
  2. the sentence could not possibly be false.
  3. the sentence could not possibly be without truth value.