Ambiguity in Negation: "John did not come because of the rain"
John did not come because of the rain.
This sentence seems to allow the following two completely different interpretations.
- John did not come. And the reason was the rain.
- John came. But the reason was not the rain.
Questions
A. How does this ambiguity arise? Is it because of negation?
B. What is the easiest way to avoid this ambiguity?
Solution 1:
The ambiguity occurs because of the way that adjectives bind to the (normally) closest phrase.
Consider a parallel:
I still have sand in my shoes from Hawaii.
What is from Hawaii? The sand or the shoes?
(Edit 1. Note that there is an ambiguity in the sentence that does not involve negation.)
When I read the example, the first interpretation came to mind, probably because not was closer to come than to rain.
You could avoid the ambiguity in different ways.
(Edit 2. Removing "John didn't come because of the rain." as it does not remove the binding ambiguity.)
A. John did not come, as the torrential rain prevented him. (Slight expansion lessens the ambiguity.)
B. John came, not because of the rain, but driven by his longing for Helen. (Explanation makes it clearer in the reader's mind.)
Solution 2:
This is usually discussed under the label 'the semantic scope of negation'. If you use curly brackets to enclose a semantic unit, this becomes clear.
Your first meaning has the semantic structure {not + {John came}} + {because of the rain}, and the second has the semantic structure {not + {John came because of the rain}}.
As Jim noted, the meaning is often clear in speech, whether 'because of the rain' is said as a separate tone unit or not. In the first interpretation is constitutes another semantic unit, and so would be spoken with a separate tone unit.
In writing, for the first meaning, consider fronting 'because of the rain' because this signals that it is a separate semantic unit: Because of the rain, John did not come. I am happy with Rajah's suggestion of moving not to before because for the second meaning.