The branch of economics that studies preferences and choices as they relate to costs and benefits is the natural starting point for understanding these phenomena as they relate to tobacco/nicotine use. Many implications of substituting low-risk alternatives (e-cigarettes, smokeless tobacco) for smoking, usually referred to as ‘tobacco harm reduction’, can be derived from even simple economic analysis. But such analysis has been largely avoided, limiting understanding and creating potentially harmful myths. Illiberal policies are hidden behind indefensible assumptions that contradict basic economics. Substitution of a low risk product would be welfare-enhancing for most smokers. Some smokers will still prefer smoking to any available alternative, despite the much higher risk. But there are vanishingly few smokers for whom abstinence is a better choice than switching to a low-risk alternative. Thus there is no apparent ethical justification for anti-smoking measures that push for abstinence rather than switching.