The reverse is possible too: there are some verbs (at least savoir and pouvoir, not sure if there are others) that can be negated just with ne, without pas, although it sounds stilted and old-fashioned. You are unlikely to encounter this in the real world but it does show up in books. For example Dumbledore in the French translation of Harry Potter says “je ne puis” and “je ne sais” a fair amount.

I'm not a native speaker, but I've read that "je ne [verb]" was the standard way to negate in Old French, cognate with e.g. "yo no [verb]" in Spanish. The "pas" was originally only added for emphasis, but over time it became obligatory and the "ne" became less important.

It's almost as if, contrary to what the person three comments up says, languages evolve over time...