Nudges alter choice sets

Abstract According to a widespread view, nudges are freedom-retaining in virtue of choice set non-interference : they help agents make better choices without altering the sets of options agents choose amongst. The present paper argues that this view is false and that nudges in fact do both add and remove options from agents’ choice sets. Two distinct lines of argument support this case. The primary argument appeals to the role of attention and salience in shaping agents’ choice sets in rich environments. The secondary argument analyses options as bundles of behavioural outputs and relevant considerations, where nudges alter these bundles. I argue that the received concept of nudge as something that does not alter choice sets and is based on behavioural science is inconsistent: choice set non-interference can only be endorsed if the role of salience in shaping choice sets, a crucial aspect of human bounded rationality, is ignored. Choice set non-interference, a foundational assumption in the nudge literature, ought therefore to be abandoned. This is a far-reaching implication: a central premise of the nudge programme fails, and its broader justification must be rebuilt accordingly. The conclusion generalizes beyond nudges to behavioral policy more broadly. While appreciating that choice sets are shaped by nudges does not require us to consider them as freedom-undermining, it does require proponents of nudges to abandon choice set non-interference for a more nuanced account of the relevant sense of freedom, and to revise their arguments for nudges accordingly.