On the redundancy of ne and pas

Question

To say that I don't know, I use

Je ne sais pas.

To me that means

I not I-know not.

So either ne or pas is redundant.

Can you just leave one out?

Also, if I is already encoded into sais, why the Je?

Can you just say:

Ne sais

Answer 1

Outside the imperative mood, a conjugated verb requires a subject in French so you can't drop the pronoun here. I believe that's similar in English. Spanish and Italian on the other hand do not require pronouns, one reason is their verbal forms are clearly distincts phonetically.

About the redundancy, spoken French ususally drops the ne but in written French, the split negative is the norm. Technically ne and pas do not play the same role so they can't both be word-by-word translated to not.

There have already been dozens of questions about them:

Does "ne" not negate words that are already negative?

Does `ne` and `pas` have a different meaning?

Negation without pas

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