Singer argues that if we are able to prevent something bad from happening without causing something comparably bad to happen ourselves, then we are obligated to do it. It follows that people in relatively affluent countries are morally required to come to the assistance of those suffering from famine, malnutrition, lack of shelter, and other preventable evils in poor countries. This is a question not of charity but of duty; giving as much as we can without sacrificing something of comparable moral importance to what those in need are lacking is not morally optional. In different terms, it is obligatory, not supererogatory. It makes no difference where the preventable evil might be taking place, who might be suffering from it, or what others in our situation of relative affluence might be doing in response. Singer acknowledges that his argument has radical implications both for our moral conceptual scheme (e.g., for where we draw the line between justice and charity) and for the way of life we have come to take for granted, but he denies that these have any bearing on the soundness of his view.