Whether or not: the unwanted implicature

It has become widely accepted to use "whether or not" as a shortcut, such as saying

"I don’t know whether or not I should go"

instead of

I don’t know whether I should go or stay.

In the former example, "whether" is not being used correctly since the alternative has not been introduced, but since it’s implied, you’re certainly not going to hear many people complain about its use in this way, especially in informal situations.

In the latter example, "whether" is used as intended, introducing two well-defined alternatives.

What is clearly incorrect is using "whether or not" with well-defined alternatives, such as

I don’t know whether or not I should go or stay.

since this example introduces more possibilities than intended.

In the example, it introduces four alternatives:

i. going,
ii. not going,
iii. staying, and
iv. not staying, as opposed to the intended two.

This example mirrors some other issues.

Enough people use "whether or not" with well-defined alternatives for it to have gained acceptance.

**************GRICE'S CAVEAT*****************

However, acceptance of something that is not logical is not the best way to communicate.


“I don’t know whether or not I should go or stay”

two alternatives, not four…your claim that four alternatives are introduced is not logical…not the statement.


I don’t know whether I should stay or go gives two alternatives as does I don’t know whether or not I should stay; the combination of the two–I don’t know whether or not I should stay or go–is redundant.



On the other hand, there is the following case:

“I will go whether or not it rains.”

In this case, “whether or not” is used in place of “regardless of whether.” Is the latter preferable in such a case?

And what about the following instance:

“I don’t know whether I should go.”

Would this be better, stylistically, than “I don’t know if I should go”?

Or not?