Not both of them are scientists. (One is a scientist, the other is not.) (Not both of them are scientists. One is a scientist, the other is not.)
Not all countries in the world have enjoyed freedom of the press. (Some countries have enjoyed, some have not.) (Not all countries in the world have enjoyed freedom of the press. -Some countries have enjoyed, some have not.)
I do not like both of these paintings. (I like one of the paintings, while I don’t like the other one.)
Neither of the two is a scientist. (Neither of the two is a scientist.)
No country in the world has enjoyed freedom of the press. (No country in the world has enjoyed freedom of the press.)
I like neither of the paintings. (I like neither of the paintings.)
(I do not like both of these paintings. -I like one of the paintings, while I don’t like the other one.)
When the absolute extreme words such as all, every, both, always, and necessarily are used with “not”, the word is negated partially – this is called “Partial Negation”. For example, “not+all” means “some are, but some aren’t”.
E.g.) Not all my brothers are at home. = Some of my brothers are at home, and some of my brothers are not at home. (Not all my brothers are at home. = Some of my brothers are at home, and some of my brothers are not at home.)
On the contrary, “Complete Negation” can be expressed by the following methods: 1)By using “No” or “None” E.g.)No one is going to the party. (No one is going to the party.) None of my friends are going to the party. (None of my friends are going to the party.)
2)By using “Not + either/neither” E.g.)I do not like either of the paintings. (I do not like either of the paintings.) I like neither of the paintings. (I like neither of the paintings.)
3)By using “Not + any” E.g.)I do not have any money. (I do not have any money.)