It is pointless to object to choice architecture or nudging as such. Choice architecture cannot be avoided. Nature itself nudges; so does the weather; so do spontaneous orders and invisible hands. The private sector inevitably nudges, as does the government. It is reasonable to object to particular nudges, but not to nudging in general. In this context, ethical abstractions (for example, about autonomy, dignity, and manipulation) can create serious confusion. To make progress, those abstractions must be brought into contact with concrete practices. Nudging and choice architecture take diverse forms, and the force of an ethical objection depends on the specific form. If welfare is our guide, much nudging is actually required on ethical grounds. If autonomy is our guide, much nudging is also required on ethical grounds.