Mechanistic explanations and the ethics of nudging

Stefano Calboli, Vincenzo Fano


Abstract: Nudges have proven to be effective tools for steering citizens toward desirable behaviors and make valuable additions to any policy-maker’s toolbox. Disappointingly, however, there are no mechanistic explanations for how nudges work, leaving policy-makers unable to explain what happens when they are implemented. This paper identifies some neglected ethical implications of the resulting citizens lack of awareness of such mechanisms. We first examine mechanistic explanations in relation to citizens’ understanding on how they work. Then, we look at mechanistic explanations in light of the suggestion advanced by some ethicists that nudges be considered ethically acceptable in modern liberal democracies provided the explicit transparency of the nudges employed.

Keywords: Nudge; Ethics of Nudging; Mechanistic Evidence; In-principle Transparency; Explicit Transparency

Spiegazioni meccanicistiche e l’etica dei nudges

Riassunto: I nudge si sono rivelati strumenti di policy efficaci nello "spingere gentilmente" i cittadini verso comportamenti considerati desiderabili. Per questa ragione i nudge sono considerati validi strumenti della cassetta degli attrezzi di un policymaker. Tuttavia, è in qualche modo deludente la mancanza di spiegazioni meccanicistiche dei nudge, dalla quale risulta l'incapacità dei policymaker di spiegare quello che succede quando i nudge vengono effettivamente implementati. Questo articolo identifica alcune implicazioni etiche finora trascurate connesse alla inconsapevolezza da parte dei cittadini circa i meccanismi che governano i nudge. Da una parte, le nostre considerazioni metteranno in relazione le spiegazioni meccanicistiche con la comprensione dei nudge da parte dei cittadini. Dall'altra parte, metteremo in relazione le spiegazioni meccanicistiche con il concetto di trasparenza esplicita, ossia la richiesta avanzata da alcuni eticisti al fine di considerare i nudge eticamente accettabili nelle moderne democrazie liberali.

Parole chiave: Nudge; Etica dei nudge; Spiegazioni meccanicistiche; Trasparenza implicita; Trasparenza esplicita

Parole chiave

Nudge; Ethics of Nudging; Mechanistic Evidence; In-principle Transparency; Explicit Transparency

Full Text


Riferimenti bibliografici

ALESINA, A., PASSARELLI, F. (209). Loss aversion in politics. In: «American Journal of Political Science», vol. LXIII, n. 4, pp. 936-947.

BARGAIN, O., AMINJONOV, U. (2020). Trust and compliance to public health policies in times of Covid-19. In: «Journal of Public Economy», vol. CXCII - doi: 10.1016/j.jpubeco.2020.104316.

BARON, J. (2007). Thinking and deciding, Cambridge University Press, Cambridge, 4th edition.

BARTON, A., GRÜNE-YANOFF, T. (2015). From libertarian paternalism to nudging - and beyond. In: «Review of Philosophy and Psychology», vol. VI, n. 3, pp. 341-359.

BENARTZI, S., BESHEARS, J., MILKMAN, K.L., SUNSTEIN, C.R., THALER, R.H., SHANKAR, M., TUCKER-RAY, M., CONGDON, W.J., GALING, S. (2017). Should governments invest more in nudging?. In: «Psychological Science», vol. XXVIII, n. 8, pp. 1041-1055.

BENARTZI, S., THALER, R.H. (1995). Myopic loss aversion and the equity premium puzzle. In: «The Quarterly Journal of Economics», vol. CX, n. 1, pp. 73-92.

BICCHIERI, C., FATAS, E., ALDAMA, A., CASAS, A., DESHPANDE, I., LAURO, M., PARILLI, C., SPOHN, M., PEREIRA, P., WEN, R. (2021). In science we (should) trust: Expectations and compliance across nine countries during the COVID-19 pandemic. In: «PLoS ONE», vol. XVI, n. 6, Art. Nr. e0252892 – doi: 10.1371/journal.pone.0252892.

BLAIR, R.A., MORSE, B., TSAI, L.L. (2017). Public health and public trust: Evidence from the ebola virus dis-ease epidemic in Liberia. In: «Social Science and Medicine», vol. CLXXII, pp. 89-97.

BOVENS, L. (2009). The ethics of nudge. In: T. GRÜNE-YANOFF, S.O. HANSSON (eds.), Preference change: Approaches from philosophy, economics and psychology, Springer, Berlin/New York, pp. 207-219.

BREHM, J.W. (1966). A theory of psychological reactance, Academic Press, Boston/London/New York.

BRUNS, H., KANTOROWICZ-REZNICHENKO, E., JONSSON, M.L., RAHALI, B. (2018). Can nudges be transparent and yet effective?. In: «Journal of Economic Psychology», vol. LXV, Issue C, pp. 41-59.

CAMERER, C. (1999). Behavioral economics: Reunifying psychology and economics. In: «Proceedings of the National Academy of Sciences», vol. XCVI, n. 19, pp. 10575-10577.

CASAL, S., GUALA, F., MITTONE, L. (2019). On the transparency of nudges: An experiment, CEEL Working Papers n. 1902.

CHAPMAN, G.B., LI, M., COLBY, H., YOON, H. (2010). Opting in vs opting out of influenza vaccination. In: «Journal of the American Medical Association», vol. CCCIV, n. 1, pp. 43-44.

CHEN, M., LAKSHMINARAYANAN, V., SANTOS, L. (2006). How basic are behavioral biases? Evidence from capuchin monkey trading behavior. In: «Journal of Political Economy», vol. CXIV, n. 3, pp. 517-537.

FELSEN, G., CASTELO, N., REINER, P.B. (2013). Decisional enhancement and autonomy: Public attitudes towards overt and covert nudges. In: «Judgment and Decision Making», vol. VIII, n. 2, pp. 202-213.

FELSEN, G., REINER, P.B. (2015). What can neuroscience contribute to the debate over nudging?. In: «Review of Philosophy and Psychology», vol. VI, n. 3, pp. 469-479.

FESTA, R., CEVOLANI, G. (2013). Giochi di società: teoria dei giochi e metodo delle scienze sociali, Mimesis, Milano.

FIGUEIRAS, M.J., GHORAYEB, J., COUTINHO, M.V.C., MARÔCO, J., THOMAS, J. (2021). Levels of trust in information sources as a predictor of protective bealth behaviors during COVID-19 pandemic: A UAE cross-sectional study. In: «Frontiers in Psychology», vol. XII, Art.Nr. 633550 – doi: 10.3389/fpsyg.2021. 633550.

FISCHHOFF, B. (1975). Hindsight is not equal to fore-sight: The effect of outcome knowledge on judgment under uncertainty. In: «Journal of Experimental Psychology: Human Perception and Performance», vol. I, n. 3, pp. 288-299.

FONG, G.T., KRANTZ, D.H., NISBETT, R.E. (1986). The effects of statistical training on thinking about everyday problems. In: «Cognitive Psychology», vol. XVIII, n. 3, pp. 253-292.

GIGERENZER, G. (1998). Why heuristics work. In: «Perspectives on Psychological Science», vol. III, n. 1, pp 20-29.

GIGERENZER, G. (2015). On the supposed evidence for libertarian paternalism. In: «Review of Philosophy and Psychology», vol. VI, n. 3, pp. 361-383.

GOLDENBERG, M.J. (2021). Vaccine hesitancy: Public trust, expertise, and the war on science (science, values, and the public), University of Pittsburgh Press, Pittsburgh.

GRAUPMANN, V., JONAS, E., MEIER, E., HAWELKA, S., AICHHORN, M. (2011). Reactance, the self, and its group: When threats to freedom come from the ingroup versus the outgroup. In: «European Journal of Social Psychology», vol. XLII, n. 2, pp. 164-173.

GRÜNE-YANOFF, T. (2012). Old wine in new casks: Libertarian paternalism still violates liberal principles. In: «Social Choice and Welfare», vol. XXXVIII, n. 4, pp. 635-645.

GRÜNE-YANOFF, T. (2016). Why behavioural policy needs mechanistic evidence. In: «Economics and Philosophy», vol. XXXII, n. 3, pp. 463-483.

GRÜNE-YANOFF, T., MARCHIONNI, C., FEUFEL, M.A. (2018). Toward a framework for selecting behavioural policies: How to choose between boosts and nudges. In: «Economics and Philosophy», vol. XXXIV, n. 2, pp. 243-266.

HANSEN, P.G., JESPERSEN, A.M. (2013). Nudge and the manipulation of choice. In: «European Journal of Risk Regulation», vol. IV, n. 1, pp. 3-28.

HAUSMAN, D. (2012). Preference, value, choice, and welfare, Cambridge University Press, Cambridge.

HOUSE OF LORDS, SCIENCE AND TECHNOLOGY SELECT COMMITTEE, Behaviour change (Second report), 2011, London, United Kingdom – available at URL:

JACHIMOWICZ, J.M., DUNCAN, S., WEBER, E.U., JOHN-SON, E.J. (2019). When and why defaults influence decisions: A meta-analysis of default effects. In: «Behavioural Public Policy», vol. III, n. 2, pp. 159-186.

JOHNSON, E.L., GOLDSTEIN, D. (2003). Do defaults save lives?. In: «Science», vol. CCCII, n. 5649, pp. 1338-1339.

KAHNEMAN, D. (2011). Thinking, fast and slow, Macmillan, New York.

KAHNEMAN, D., SIBONY, O., SUNSTEIN, C.R. (2021). Noise: A flaw in human judgment, William Collins, London.

KAHNEMAN, D., SLOVIC, P., TVERSKY, A. (1982), Judgment under uncertainty: Heuristics and biases, Cambridge University Press.

KAHNEMAN, D., TVERSKY, A. (1979). Prospect theory: An analysis of decision under risk. In: «Econometrica», vol. XLVII, n. 2, pp. 263-292.

KANTOROWICZ‐REZNICHENKO, E., KANTOROWICZ, J. (2021). To follow or not to follow the herd? Transparency and social norm nudges. In: «Kyklos», vol. LXXIV, n. 3, pp. 362-377.

LEHMANN, B.A., CHAPMAN, G.B., FRANSSEN, F.M., KOK, G., RUITER, R.A. (2016). Changing the default to promote influenza vaccination among health care workers. In: «Vaccine», vol. XXXIV, n. 11, pp. 1389-1392.

LEVINE, D.K. (2012). Is behavioral economics doomed? The ordinary versus the extraordinary, Open Book, Cambridge.

LOEWENSTEIN, G., BRYCE, C., HAGMANN, D., RAJPAL, S. (2015). Warning: You are about to be nudged. In: «Behavioral Science and Policy», vol. I, n. 1, pp. 35-42.

MARCHIONNI, C., REIJULA, S. (2019). What is mechanistic evidence, and why do we need it for evidence-based policy?. In: «Studies in History and Philosophy of Science – Part A», vol. LXXIII, pp. 54-63.

MICHAELSEN, P., NYSTRÖM, L., LUKE, T.J., JOHANSSON, L., HEDESSTRÖM, M. (2020). Are default nudges deemed fairer when they are more transparent? People’s judgments depend on the circumstances of the evaluation. In: «PsyArxiv Preprints» - doi: 10.31234/

MILKMAN, K.L., CHUGH, D., BAZERMAN, M.H. (2009). How can decision making be improved?. In: «Perspectives on Psychological Science», vol. IV, n. 4, pp. 379-383.

MILLER, C.H., LANE, L.T., DEATRICK, L.M., YOUNG, A.M., POTTS, K.A. (2007). Psychological Reactance and Promotional Health Messages: The effects of con-trolling language, lexical concreteness, and the restoration of freedom. In: «Human Communication Re-search», vol. XXXIII, n. 2, pp. 219-240.

MIRON, A.M., BREHM, J.M. (2006). Reactance theory – 40 years later. In: «Zeitschrift für Sozialpsychologie», vol. XXXVII, n. 1, pp. 9-18.

MOREWEDGE, C., YOON, H., SCOPELLITI, I., SYMBORSKI, C., KORRIS, J., KARIM, K. (2015). Debiasing decisions: Improved decision making with a single training intervention. In: «Policy Insights from the Behavioral and Brain Sciences», vol. II, n. 1, pp. 129-140.

MOYER-GUSE, E., NABI, R.L. (2010). Explaining the effects of narrative in an entertainment television program: Overcoming resistance to persuasion. In: «Human Communication Research», vol. XXXVI, n. 1, pp. 26-52.

NATHAN, M.J. (2021). Black boxes: How science turns ignorance into knowledge, Oxford University Press, Oxford.

NOVEMSKY, N., KAHNEMAN, D. (2005). The boundaries of loss aversion. In: «Journal of Marketing Research», vol. XLII, n. 2, pp. 119-128.

O’DONOGHUE, T., RABIN, M. (2015). Present bias: Les-sons learned and to be learned. In: «American Eco-nomic Review», vol. CV, n. 5, pp. 273-279.

OECD (2017). Behavioural insights and public policy: Lessons from around the world, OECD Publishing, Paris.

OSMAN, M., MCLACHLAN, S., FENTON, N., NEIL, M., LÖFSTEDT, R., MEDER, B. (2020). Learning from behavioural changes that fail. In: «Trends in Cognitive Sciences», vol. XXIV, n. 12, pp. 969-980.

PETTIT, P. (2012). On the people’s terms: A republican theory and model of democracy, Cambridge Universi-ty Press, Cambridge.

QUICK, B.L., STEPHENSON, M.T. (2008). Examining the role of trait reactance and sensation seeking on perceived threat, state reactance, and reactance restoration. In: «Human Communication Research», vol. XXXIV, n. 3, pp. 448-476.

RACHLINSKI, J.J., WISTRICH, A.J. (2018). Gains, losses, and judges: Framing and the judiciary. In: «Notre Dame Law Review», vol. XCIV, n. 2, pp. 521-582.

REBONATO, R. (2012). Taking liberties: A critical examination of libertarian paternalism, Palgrave-Macmillan, London/New York.

SELLIER, A., SCOPELLITI, I., MOREWEDGE, C. (2019). Debiasing training improves decision making in the field. In: «Psychological Science», vol. XXX, n. 9, pp. 1371-1379.

SIMON, H.A. (1955). A behavioral model of rational choice. In: «Quarterly Journal of Economics», vol. LXIX, n. 1, pp. 99-118.

SOLL, J.B., MILKMAN, K.L., PAYNE, J.W. (2016). A user’s guide to debiasing, In: G. KEREN, G. WU (eds.), The Wiley Blackwell handbook of judgment and decision making, Wiley-Blackwell, New York/London, pp. 924-951.

SONG, H., MCCOMAS, K.A., SCHULER, K.L. (2018). Source effects on psychological reactance to regulatory policies: The role of trust and similarity. In: «Science Communication», vol. XL, n. 5, pp. 591-620.

STEINDL, C., JONAS, E., SITTENTHALER, S., TRAUT-MATTAUSCH, E., GREENBERG, J. (2015). Under-standing psychological reactance. In: «Zeitschrift für Psychologie», vol. CCXXIII, n. 4, pp. 205-214.

STRAHAN, E., ZANNA, M. (2002). Subliminal priming and persuasion: Striking while the iron is hot. In: «Journal of Experimental Social Psychology», vol. XXXVIII, n. 6, pp. 556-568.

SUNSTEIN, C.R. (2016). Do people like nudges?. In: «Administrative Law Review», vol. LXVIII, n. 2, pp. 177-232.

THALER, R.H., BENARTZI, S. (2004). Save more tomorrowTM: Using behavioral economics to increase employee saving. In: «Journal of Political Economy», vol. CXII, n. S1, pp. 164-187.

THALER, R.H., BENARTZI, S. (2013). Behavioral economics and the retirement savings crisis. In: «Chicago Booth Review», available at URL:

THALER, R.H., SUNSTEIN, C. (2021). Nudge: The final edition, Penguin Books, New York.

TRAPPEY, C. (1996). A meta‐analysis of consumer choice and subliminal advertising. In: «Psychology and Marketing», vol. XIII, n. 5, pp. 517-530.

TVERSKY, A., KAHNEMAN, D. (1991). Loss aversion in riskless choice: A reference-dependent model. In: «The Quarterly Journal of Economics», vol. CVI, n. 4, pp. 1039-1061.

WACHNER, J., ADRIAANSE, M., DE RIDDER, D. (2020). The influence of nudge transparency on the experience of autonomy. In: «Comprehensive Results in Social Psychology», doi: 10.1080/23743603.2020.1808782.

WASON, P., EVANS, J. (1974). Dual processes in reasoning?. In: «Cognition», vol. III, n. 2, pp. 141-154.


Copyright (c) 2022 Stefano Calboli, Vincenzo Fano

URLdella licenza:

Rivista internazionale di Filosofia e Psicologia - ISSN: 2039-4667 (print) - E-ISSN: 2239-2629 (online)

Registrazione al Tribunale di Milano n. 634 del 26-11-2010 - Direttore Responsabile: Aurelia Delfino

Web provider Aruba spa - Loc. Palazzetto, 4 - 52011 Bibbiena (AR) - P.IVA 01573850516 - C.F. e R.I./AR 04552920482

Licenza Creative Commons
Dove non diversamente specificato, i contenuti di Rivista Internazionale di Filosofia e Psicologia sono distribuiti con Licenza Creative Commons Attribuzione 4.0 Internazionale.