 It is natural to restrict ‘injustice’ to actions caused by other persons. So, we might think that if \(B\) is drowning because \(A\) pushed her overboard, \(B\) is the victim of injustice; whereas, if she accidentally fell overboard, \(B\) is the victim of natural misfortune. Some philosophers (such as libertarians) have argued that these natural misfortunes do not trigger duties of justice for others. However, this position is far from universally accepted. Others, like Goodin, argue vulnerability triggers duties of justice regardless of the source of the duress. So, even if \(A\) is not responsible for \(B\) being in the water, justice may require that he provide her with aid. If \(A\) has such a moral duty to aid \(B\), but threatens to withhold aid in order to induce \(A\) to pay him, he coerces her (according to many prominent analyses of coercion) and when \(A\) benefits from this coercion, he exploits \(B\).