I always think of it as -
What a sentence denotes is rarely reliable information;
but the fact that the sentence was stated means something, with the right context, including a model of the speaker/writer.
Someone says "X" and it doesn't tell you a thing about whether "X" is the case, but it always tells you they wanted to tell you "X" for some reason.
Noise might not contain information but the presence or absence of noise does.