To take an example involving two parties in a court of law: Adrian has a negative right to x against Clay if and only if Clay is prohibited from acting upon Adrian in some way regarding x. In contrast, Adrian has a positive right to x against Clay if and only if Clay is obliged to act upon Adrian in some way regarding x. A case in point, if Adrian has a negative right to life against Clay, then Clay is required to refrain from killing Adrian; while if Adrian has a positive right to life against Clay, then Clay is required to act as necessary to preserve the life of Adrian.