meaning of "Not all"

[seychelles1718]

I saw that some people interchange "not all" with "some." But does "not all" also include zero, unlike "some"?

[ohthatpatrick]

NEGATIVE PHRASE TRANSLATIONS:
Not all A's are B = Some A's are ~B

Few A's are B = Most A's are ~B

No A's are B = All A's are ~B


Some statements are always "at least one", so they never have a maximum. Since "not all" translates to "some aren't", it's possible that 100% aren't.

For example, these are all true statements:
Not all NFL players are women.
Not all people who can give birth are men.
Not all planets with intelligent life on them are named Mars.

You definitely need to build the habit of translating these into
"at least one NFL player is NOT a woman"
"at least one person who can give birth is NOT a man"
"at least one planet with intelligent life on it is NOT called Mars"