English Grammar: Negatives
Unless it is tied to something quantifiable, the number zero or nought simply implies an absence of anything numerically quantifiable. In contrast, negation in language functions in a contradictory way; it invokes a connection, action, modification, etc., only to then deny it. However, a negative nearly always creates a ghostly presence of the very thing it is saying is absent. Something may well not be green, but in learning that our image and understanding of whatever it is coloured by the green whose absence is a characteristic.
This ingenious mechanism common to all languages is one of the driving forces of creativity and generators of meaning. Through it we have access to one of the primary and most fundamental of all tools for creating shades of meaning.