The objectives of the research project are to 1) analyse and assess the epistemic dimension of recent applications of the behavioural sciences to policy, 2) bring the novel perspective from the philosophy of science to advance the current debate on the reliance on the behavioural findings in policy contexts, 3) work out the reflective and critical philosophical approach to the interactions between science and policy. ‘Nudging’ is an example of an approach to regulation, elicited by the application of the behavioural sciences to policymaking. I show that the current debate on nudging and on behaviourally informed regulations overlooks several important dimensions. I address them from the perspectives not yet taken (e.g. Helen Longino’s analysis of scientific knowledge about behaviour). I show that the proponents of bringing the behavioural sciences to policy do not recognize the problems for practical applications that emerge from the plurality of approaches within the behavioural sciences.