Learn English – Difference between “not every” and “every … is not”

logicmeaningnegationword-order

I've always understood that you can order the words not and every (or similar words) in the following two ways to convey distinct logical meanings.

  • Every human is not a man. There is no human being who is a man.
  • Not every human is a man. There are human beings who are not men.

Being a non-native speaker, I learn most of my English by reading things on the internet. The thing is that I almost never see people doing it this way and this made me question my understanding.

For example, a comment on another Stack Exchange website reads:

Everything on DOS is not plain-text!

To my understanding, this sentence means that there is nothing on DOS that is plain-text, but it is clear to me that the author of the message intended a different meaning. I would correct this sentence to:

Not everything on DOS is plain-text!

Am I correct and is this mistake very commonly made or do I have a fundamental misunderstanding of this sentence structure?

Best Answer

You are correct; Karan of the superuser question you referenced made a grammatical error. It should have been as you phrased it:

Not everything in DOS is plain-text

That being said, your understanding in the two examples you posted is slightly off. It should be

Every human is not a man. There is no human being who is a man.

Not every human is a man. There are human beings who are not men.

Such logic mistakes (especially with double negatives) are very common even among native English speakers. The fact that you are able to discern the intended meaning of Karan's comment, even with its incorrect phrasing, and your excellent grammar in this post tells me that you do not at all have a fundamental misunderstanding; on the contrary, your english seems quite good.