not vs not


Tatar & Russian
I've been trying to figure out the difference between not and not

One quite reliable source ( asserts:

not “It was not as difficult as I had predicted.” (Wrong)
In a comparison involving a negative modifier such as no, not, or never, the word so, instead of as, should be used before the first adjective or adverb. This pattern is an example of archaic usage that is no longer observed by most American English speakers, but the writers of the SAT may expect you to at least be able to recognize that it is an accepted idiom. “It was not so difficult as I had predicted.” “He never ran so quickly as when his life was in danger.”

Whereas another source claims that we use not when comparing two things in terms of quality (usefulness, convenience, efficiency, etc.), e.g.

My car is not so comfortable as yours.

Does the above prompt that we should say His hair is not as white as snow?

I'd like to know if there is a difference, and if yes, what it is. Thanks.
Last edited:
  • entangledbank

    Senior Member
    English - South-East England
    I don't think there's any difference in situations; 'not so' is just more old-fashioned than 'not as', which is the usual form today - in BrE as well as AmE.

    I wouldn't use that source you referenced. It doesn't clearly distinguish between actual errors, forms that other people say are errors but the author thinks are not, and forms that the author wrongly thinks are errors.


    Tatar & Russian
    One other thought.
    Consider the sentences:

    This test is not as difficult as that one.
    This test is not so difficult as that one.

    Do these convey absolutely the same meaning?
    To me it seems that there is a slight difference between the two. Using not so makes you think the test is very difficult, whereas not as does not necessarily do.


    New Member
    German - Germany
    I was wondering about these two possiblities, too. And I was very unsure about right usage, especially because in German for 'not as much as' we say 'nicht so viel wie', and I was afraid, that this might entice me to say 'not so much as', and not any statements about old-fashioned use and any thinking about the quality of old-fashioned use of languages (not all new-fashioned stuff is well-designed).

    I hear this slight difference like you, and after having read lots of samples from anywhere in the web I feel, that there is a difference concerning an included indication of degree. In German in these cases I would tend to use 'derart' instead of 'so'.

    But I'd be happy if some native speakers could explain their own view and feeling concerning this.