Actually no! Lower numbered laws have priority over higher numbers, meaning that if they come into conflict the higher number law can be broken. While the first law says they can’t allow humans to come to harm, the zeroth law basically says that if it’s for the good of the species, they absolutely can kill or otherwise hurt individual humans.
It would technically be the fifth law.
But if you’re starting from zeroth it would be the fourth.
couldn’t that be inferred from the first law?
Actually no! Lower numbered laws have priority over higher numbers, meaning that if they come into conflict the higher number law can be broken. While the first law says they can’t allow humans to come to harm, the zeroth law basically says that if it’s for the good of the species, they absolutely can kill or otherwise hurt individual humans.