I once heard that this used to be a way to emphasize, by adding the thing you do not do. Not very clear, bit here are some examples:

- je ne marche _pas_ (I not not walk _any step_)

- je ne me bat _guerre_ (I do not fight _any war_)

- je ne coud _point_ (I do not sew _any point_)

And then slowly disconnected. All those words are still used as negations, and I cannot think of any word of negation that cannot be interpreted this way, so that might be true (but I cannot really think of more than those 3 either). What makes me doubt is what words would have persisted (why _ step_ as the one most common?)

This phenomenon is called a "Jespersen's cycle" according to Wiktionary.

https://fr.wiktionary.org/wiki/cycle_de_Jespersen

Also according to Wiktionary, "guère" is unrelated to "guerre" (war) and "ne ... guère" is therefore not the product of a Jespersen's cycle.

https://fr.wiktionary.org/wiki/gu%C3%A8re

> je ne marche _pas_ (I not not walk _any step_)

It merely means I do not walk. There's no particular connotation. It has absolutely nothing to do with pas as in a step.

> - je ne me bat _guerre_ (I do not fight _any war_)

Je ne me bat guère means "I hardly fight". No relation to war.

> - je ne coud _point_ (I do not sew _any point_)

Je ne couds point means "I don't sew". Again, no particular connotation. Point means the same as pas in this case and has nothing to do whatsoever with stitches.

You're mentioning the current, disconnected meaning, while the original author showed a possible origin of those expressions. I dont know if they're valid but they're certainly interesting and potentially right.

> It has absolutely nothing to do with pas as in a step.

"Pas" as in the negation originally came from "pas" as in a step, through expressions like "I will not walk another step".

> - je ne me bat _guerre_ (I do not fight _any war_)

This is not 'guerre' here but 'guère', which is a homonym but has no relation to 'guerre' (war). 'Guère' comes from an old French word that means 'a lot'.

Taking this into account it is clearer that "je ne me bat guère" means "I don't fight much"/"I hardly fight".

You could have picked any verb instead of 'to fight'. I suspect your other examples are equally contrived.

When speaking or even writing non formally, the "ne" are sometimes dropped. It's incorrect of course but perfectly understandable most of the time (dropping the "pas" instead is really weird but still understandable). My uninformed opinion is that this must just be a redundancy, which helps makes sure the negation is well heard, since missing it is generally catastrophic for the meaning as it generally means the opposite. Actually, in English negation can also add 2 words (do not), which also helps hearing it IMO. It also tends to be contacted. BTW I always have a problem with can vs can't, and often have to ask which one it is :)

Unintuitively, informal speaking often skips the ne but the pas is mandatory.

Je mange pas ça - I don’t eat this.

Also the second part can add nuance to the negation, fe.

Je ne mange plus ça - I don’t eat this anymore.

*Not a native speaker so there’s definitely more to it than I know.