First, I know that "not all" is partial negation. For example, "not all the numbers are 0" means there may be a number that is nonzero.
And to me, a non-native speaker of English, it seems that "all not" should be used for complete negation. However, I remember distinctly from high-school English lessons that "all not" is also partial negation.
Exactly which is it?
More specifically, suppose I say "all the numbers are not zero", does it mean every single number cannot be zero, or that there may be one or more numbers that are zero?
Best Answer
The construction you are asking about, "all-not" can be a partial negation or a complete negation depending on the context.
That is:
could mean either,
or
Pathetic, I know, but it all depends on the situation.
Regular people, who may be native speakers, sometimes (but not always!) use all-not as a partial negation in everyday speech, even though that goes counter to what you would figure from a logic point of view.
The common folk-expression "all that glitters is not gold" is an example of that. It just means "some [but not all] apparently valuable things are worthless".
People who are writing or talking about zero and non-zero numbers, as in your example, or Xs and Ys, in mine, would probably be more careful to word their statements clearly, unambiguously, and/or in accordance with logic. In that sort of context, statements like, "... but all members of the group aren't like that" should be avoided in favor of something like, "...but not all members of the group are like that".