‘UNLESS’

A related question is how do we symbolize “unless”? How, for instance, should statement

(2) be translated?

(2) Unless Thou wert INCOMPREHENSIBLE Thou wouldst not be GOD.—Cardinal Newman

It seems similar to (1): couldn’t we rephrase it

(3) If Thou weren’t INCOMPREHENSIBLE Thou wouldst not be GOD?

This suggests that “unless” is equivalent to “if not.” We can check this by a similar retranslation of (1):

(4) Unless we get the oil from GROZNY or MAIKOP, we will LOSE the war.

This works. But what about (5)?

(5) Either we get the oil from GROZNY or MAIKOP, or we will LOSE the war.

This also appears to be equivalent, thus suggesting thatis equivalent to (G

V Μ) V L. We’ll prove this equivalence in the next chapter. What it means for now is that

‘unlessp, q’ can be symbolized either by

So how should we symbolize (2) above?

7.1.3