• Autonomy
• Behaviour Modification
• Health Promotion
• Public Health Ethics

Policy makers are understandably interested—for both political and moral reasons—in following Thaler and Sunstein's recommendation to use ‘choice architecture’ (as in Cafeteria ), or other ‘nudges’, to promote desirable behaviour in ways that are allegedly compatible with personal freedom.1 Yashar Saghai's intricate analysis shows that simply maintaining the target's choice-set is insufficient to preserve the target's freedom when the nudge bypasses the target's deliberative capacities—as it is specifically designed to do.2 In his friendly amendment to Thaler and Sunstein's project, Saghai advances a more robust account of nudges in which fewer policies would count as nudges, but those that do count as nudges would be less troublesome. In this commentary, I briefly discuss several issues raised by Saghai's project, some of which go beyond the topic of nudges.

• How important is definitional salvaging? If a ‘substantially controlling’ influence were more efficacious in promoting healthy behaviours, we would have a trade-off between the efficacy of a policy and its compatibility with freedom. Saghai states that an influence can be morally permissible even if it is ‘substantially controlling’ and, therefore, does not qualify as a nudge. So even on Saghai's definitional project it is not clear how much work it does in distinguishing the morally permissible from the morally impermissible.

• The …