How does negation affect the use and understanding of "or" and "and"?

Question

I'm trying to make more sense of how negation effects how a sentence is parsed and understood if *and*'s and *or*'s are used within them.Pop quiz: You are trapped on a bus with a bomb going 50 MPH. You have a radio... (okay enough Keanu Reeves references) :-)Let's say the bomb expert says "Don't cut the red or green wires." I think that means "Do not cut the wires colored red. Do not cut the wires colored green."Now, let's say the bomb expert said on the radio "Do not cut the red and green wires", instead. Do I take that to mean:> "Do not cut the wires colored red. Do not cut the wires colored green."OR> "Do not cut the wires whose insulation has red and green stripes." ?OR> "It's okay to cut the wires colored red or the wires colored green, as long I don't cut one of each color."Which meaning should I take if the radio breaks and I can't ask follow up questions?

Answer 1

I would say that "Don't cut the red and green wires," would definitely not mean, "Don't cut either the red or the green wires," because then the advisor should have said, "Don't cut the red or green wires."

So you are correct, it should either mean, "Don't cut both the red and the green wires, but you can cut one of them," or, "Don't cut the red-and-green-striped wire." If I were in this situation, I would hope that there were not a red, a green, and a red-and-green-striped wire. If there were only a red and a green, or only a striped wire, I would assume the advisor was referring to the situation in front of me and parse his directions accordingly. If there were all three wires, I would have to agree that his instructions would be ambiguous and I should resort to some serious prayers.

However, I'm not sure that bomb disposal experts are necessarily experts in English grammar, and I might be unwilling to trust his or her usage to rule out "...red and green..." as meaning "...either red or green..."!