This is Philosophy: Critical Thinking class All of the operators that we've studied in this section on formal logic are truth-functional. That means that for any assignment of truth values to the statement letters making up a statement, there is only one truth value for the entire statement.

There are, however, operators or connectives in English that are not truth-functional. Give an example of one and show that it is not truth-functional. (this involves producing an example where one assignment of truth values to the component statements leads sometimes to a true compound statement and sometime to a false compound statement)

To help you out a little, I'll give you an example. You can't use this example or any variant of it.

The English connective "President Briggs knows that..." This connective functions grammatically like the ~ : you can put it in front of any grammatical statement and you'll get a grammatical statement. To show that it's not truth functional, just come up with two true statements, one of which President Briggs knows and one that he doesn't know, and you've proved that the connective is not truth functional. So, for example, "He is president of Berry College" and "my cat's name is Spenser." The latter claim is true but I've never told President Briggs about my cat and his name, so he surely does not know.