 In discussing enforceable duties to give evidence or Samaritan aid, Mill claims that the failure to confer benefits constitutes harm. But it is not in general true that the failure to provide benefits always counts as a harm. In many cases it seems not to. You would benefit me by transferring all your savings to my bank account (let us assume); it doesn’t follow that your failure to do so harms me. Why not? Presumably, because we assess harms counterfactually: if x harms me, it makes me significantly worse off than I would have been otherwise. This makes clear that harms are assessed relative to some baseline. It is an interesting question how to set the baseline. But the baseline cannot be set by the restriction on liberty itself; that would convert all failures to benefit into harms. The baseline must have some independent rationale. Consider Mill’s example of Good Samaritan laws. A classic example of the sort of Samaritan duty that Mill favors would be the requirement to save a drowning child when I could do so at little cost or risk to myself. It is not clear that my failure to rescue harms the child. Have I made the child worse-off than he would otherwise have been? Well, relative to what baseline? Of course, I have made him worse-off relative to the baseline situation in which Good Samaritanism is compulsory. But why select that baseline? I haven’t made him worse-off relative to the situation he would have been in had I not been there. By hypothesis, he would have drowned in my absence. If so, it is not clear that I harm the person whom I fail to rescue. This is not to deny that my failure to rescue is wrong and perhaps that the law ought to compel aid in such cases. But it does raise questions about whether we can justify Good Samaritan laws by appeal to the harm principle.