The ideas and tools popularised under the banner of “nudge theory” have gained traction in the public and private sectors - and so, too, have ethical concerns regarding their use. Nudge theory, as envisioned by Richard Thaler and Cass Sunstein, assumes beneficent choice architects who help people make decisions that improve their well-being (“pro-self” nudges), or encourage behaviours supportive of broader social or environmental goals (“pro-social” nudges). However, critics have long questioned the ethicality of nudging on the grounds that the practice is often non-transpa...