What is the grammatically correct response to the question "Can you see me?":
"Of course I can, why couldn't I?"
"Of course I can, why wouldn't I?"
To me the second one seems correct, but I can't find a proper grammatical rule for why that is so. Since could is based on the ability of a person to do something it kind of fits the context, but it doesn't sound correct to me. Would, on the other hand, represents willingness rather than ability to do something so it doesn't fit the context, but sounds right.
The only reason to my mind why using would is the correct way is because it is in the form of question and therefore implying a hypothetical situation wherein lies an unknown condition which is the reason why one person would not be able to see the other.