Different word for not needed

Hello mates!

Would somebody please shed light on usage ‘need not’ as opposed to ‘don’t need’? For instance, We need not leave family and go to forest for spiritual effort. Why it wasn’t made up like this We don’t need to leave family and go…
My guess is that it expresses different meanings:
we need not may imply it’s better that we not leave
we don’t need may be interpreted like there is no need to leave
As I said, these are just assumptions.

Thanks in advance!

It’s the same meaning, but «need not» sounds more old-fashioned to me.

Your sentence sounds ungrammatical by the way, there need to be some articles in there. We need not leave our/the family and go to the forest for spiritual rituals(?).

I agree on both counts. I think that it might be possible to have a different nuance, but with the source sentence it’s hard to judge because it isn’t grammatical as a whole.

timpeac, Askalon
Thanks for joining the discussion
I just picked the first sentence my eyes laid upon after googling ‘need not’…
Here is another, hopefully grammatically correct, example:

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Look to see your comments! Thanks!

timpeac, Askalon
Thanks for joining the discussion
I just picked the first sentence my eyes laid upon after googling ‘need not’…
Here is another, hopefully grammatically correct, example:

This essay question has been a hallmark of the HBS application for many years. Due to its top billing, this question could be the first element of your file that the adcom reads, making this response a great opportunity to present the reader with three strong stories that introduce the major themes of your candidacy. Each accomplishment can be presented as a stand-alone section here, so you needn’t be overly concerned about composing a seamless narrative.

Look to see your comments! Thanks!

This just sounds like a more formal version of «don’t need to» here.

This just sounds like a more formal version of «don’t need to» here.

Exactly, this is a verb that (according to modern syntactic theory) moves from a position after negation ‘not’, to before negation (like other modals like must/can, etc). However need is special in that it has the ability to move behind negation and can do it optionally, and this explains the difference between:

You need not do that. (It is not neccesary for you to do that)
You must not do that. (It is neccessary for you not to do that)

The one with ‘must’ is a categorical neccessity for you to not do something, while the version with ‘need’ is more like there is no necessity for you to do something. Modern English generally uses the position where it doesn’t move, but it certainly can, a lingering trend of what most verbs used to do in older English. When it doesn’t move, we have do-insertion, and when it moves, it doesn’t need do-insertion, so it can act in a way that’s very similar to a) modals one the one hand and b) ordinary lexical verbs on the other.

More info can be found in 4.6 (p. 161) of ‘Analysing English Sentences’ by Andrew Radford.

I can’t remember I’ve ever heard an American use »Need not»’.
On the other hand »Must not» is very much alive in formal US English.

That’s more than likely to be true.
It’s in Britain that these sort of archaisms are normally used, generally not in any of the other Home Englishes.

However I don’t doubt there will be Americans that have heard / used it.

This syntactic distinction is also present for «have to» and «don’t have to», which many learners of English think are opposites of each other when they are not.
When you have «have to», it (structurally) would be in a position before negation (like «must», hence it’s almost identical meaning), but when using «don’t have to», this is expressing the non-necessity of something rather than the necessity to not do something, because it’s behaving like ‘need’. The structural position changes the fact of whether the (semi-)modal has narrow or wide scope over the clause or not. Normally, modals after negation have narrow scope and are to do with the non-necessity of completing an action, while modals that are pre-negation are to do with the necessity of not doing something.

You need not do that. (narrow scope, verb has moved).
You don’t need to do that. (narrow scope, verb hasn’t moved).
You don’t have to do that. (narrow scope, verb hasn’t moved).

You must not do that (wide scope)
You can not do that (wide scope)
You should not do that (wide scope)

I think I’m getting too much into syntax here though for a normal learner of English, sorry!

Just one more clarification needed… narrow and wide scope you referred to in some previous post correspond to it’s not necessary and it’s necessary not respectively?

Yeah, I am just repeating terminology I have read about this issue, I’m not sure I fully understand the reasoning behind these labels, but you’re completely right yes. When you are being ordered not to do something, the modal has wide scope over negation and when you’re being told it’s not necessary for you to do something, the modal has narrow scope.

But you really don’t need to understand these to fully understand how they work in English. I shouldn’t have mentioned it really.
As long as you know that «need not» and «must not» can be represented by your sentences in blue, that’s all you need to know.

You must not go outside!
It’s necessary for you not to go outside!

You need not go outside.
It’s not necessary to go outside (but you can if you want).

Edit: Also remember that don’t need to is the same thing, it’s more normal to use this way but it’s also possible (at least in BE) to move it so it looks like «must not».