“I ain’t got no money”
Why does the phrase "I ain't doing nothing" mean "I am doing nothing"?
According to me, "I ain't doing nothing" should translate to "I am not doing nothing", which implies that "I am doing something".
Multiple negation has long been a feature of English. It continues to be so in nonstandard dialects, but is no longer allowed in Standard English. It isn’t a case of one negative cancelling another. Rather, the greater the number of negatives, the greater the force of the negation. If you think it’s illogical, try telling that to the French, whose standard form of the language features the two negatives ne and pas used together.