 Ross does not think the five duties are of equal initial weight. The duty of non-maleficence is weightier than the duty to promote a maximum of aggregate good (RG 21, 22; FE 75, 130n1). He writes: ‘We think the principle ‘do evil to no one’ more pressing than the principle ‘do good to every one’, except when the evil is very substantially outweighed by the good’ (FE 75). It takes substantial (net) benefit to justify intentionally harming someone. It would be wrong to harm someone to promote only a marginal (net) benefit (contra utilitarianism).