Nudge

Also called: Nudge theory · Topic: Schools of Economic Thought and Economic Laws · NCERT: Beyond NCERT

Meaning

A nudge is a change in the way choices are shown to people, through tools like defaults, reminders and social norms. It moves behaviour in a predictable direction without banning any option and without changing incentives (money rewards or penalties) much. The idea comes from Richard Thaler and Cass Sunstein's book Nudge (2008).

It matters because governments can use it to change behaviour cheaply, for example on saving, health, sanitation or giving up subsidies, while people stay free to choose. India's Economic Survey 2018-19 gave it a full chapter [2].

Explanation

Why nudges work: Homo sapiens, not Homo economicus

• Classical and neoclassical economics (from Adam Smith to Marshall) assumes a Homo economicus. This is a perfectly rational person who knows every option, calculates correctly and always acts in their own best interest.
• Behavioural economics studies how real people actually behave:
• they have limited attention;
• they follow habits;
• they copy others;

• they stay with whatever is already set.

• The Economic Survey 2018-19 said that real people are not the "impractical robots" of classical economics. It added that behavioural economics is especially useful in India, where social and religious norms strongly shape behaviour [1].

• Policy lesson: design policy for Homo sapiens (real humans), not for Homo economicus [1][2].

Tools of a nudge: choice architecture and defaults

• Choice architecture: designing the setting in which people choose. It covers:
• the order in which options are shown;
• the default (what happens if you do nothing);

• the framing (how the choice is worded).

• Default option: the choice that applies if a person takes no action.

• People tend to keep what is already set. This is status quo bias (preferring things as they are).

• So a well-chosen default is one of the strongest nudges.

• Other tools: reminders, and social norms (telling people that "most others already do this").

• Test for what counts as a nudge:
• Putting fruit at eye level in a canteen is a nudge, because junk food is still available.

• Banning junk food is not a nudge, because it removes a choice.

• Classic examples:

• Auto-enrolment in pensions: workers are enrolled automatically and must act to leave. Participation rises sharply.
• Opt-out organ donation (as in Spain): everyone counts as a donor unless they say no. Donor rates rise.

Worked example (numbers are for illustration only):

Design	What the worker must do	Result (100 workers)	Participation
Opt-in	Fill a form to join	40 join	40/100 = 40%
Opt-out	Fill a form to leave	10 leave, 90 stay	90/100 = 90%

• The options and the money are the same in both designs.
• Only the default changed, yet participation rose by 50 percentage points.

The philosophy: libertarian paternalism

• Libertarian paternalism is the idea behind nudges. It has two halves:
• Paternalism: the state steers people towards choices that are better for them.

• Libertarian: people remain free to choose otherwise, and nothing is banned.

• Behavioural insights (OECD definition): lessons from the behavioural and social sciences, including decision-making, psychology, cognitive science, neuroscience and how organisations behave. Governments use them to make policies work better [9].

Limits and critiques

• Manipulation: nudges work below conscious thought, so people may not notice they are being steered.
• Who decides "better"? The government may be wrong, or it may have its own interests.
• Sludge: the opposite of a nudge. Sludge is friction that blocks good choices, such as long forms, many documents or repeated office visits.

• Example: a welfare scheme with a 10-page application form loses eligible people because of sludge, not because they don't need the scheme.

• Small effects: compared with hard tools like taxes, subsidies, bans and laws, nudges often change behaviour only modestly.

In India

• Economic Survey 2018-19, Vol. 1, Chapter 2: "Policy for Homo Sapiens, not Homo Economicus: Leveraging the Behavioural Economics of 'Nudge'". It was tabled by Finance Minister Nirmala Sitharaman [1][2].
• The Survey's three principles:
• (i) Stress the beneficial social norm. Tell people that most others already do the right thing.
• (ii) Change the default option. Make the desired choice the automatic one.

• (iii) Repeated reinforcement. Repeat the message until the habit sticks.

• Examples the Survey used:

• Swachh Bharat Mission: used social norms and made the message against open defecation clear and visible [1].
• Beti Bachao Beti Padhao: cited as a success. The Survey proposed a reframe called "BADLAV" (Beti Aapki Dhan Lakshmi Aur Vijay Lakshmi), which shows daughters as wealth and victory, not a burden [1].
• LPG "Give It Up" campaign (2015): households that could pay the market price were asked to give up their LPG subsidy voluntarily.
  • More than 1.03 crore consumers had given it up by 12 December 2018 [5].
  • A later PIB release put the figure at nearly 1.04 crore [6].
  • It worked through social norms and moral appeal, with no legal force.

• Proposed nudges: tax compliance (publicly honouring top taxpayers so that paying tax brings status), savings and health.

• Schemes and missions built on nudges:

• POSHAN Abhiyaan (2018): aims to improve nutrition for children, adolescents, and pregnant and lactating women. It is run as a Jan Andolan (people's movement) [7].
  • Poshan Maah (nutrition month) is held every September to change how people eat [7].
  • The 6th Poshan Maah (2023) registered over 6 crore activities in its first 12 days [8].
  • The 7th Rashtriya Poshan Maah (2024) recorded over 10.27 crore activities [7].
• Mission LiFE (Lifestyle for Environment): launched on 20 October 2022 at the Statue of Unity, Ekta Nagar (Gujarat), with UN Secretary-General António Guterres present [3].
  • It aims to nudge individuals and communities towards a lifestyle that does not harm nature. People who live this way are called Pro-Planet People (P3) [4].
  • Its target is to mobilise at least 1 billion Indians and other global citizens during 2022-2027 [4].
  • It shifts the focus from "mindless consumption" to "mindful use" of resources [4].
• Auto-debit defaults: Atal Pension Yojana contributions are debited automatically, and PMJJBY/PMSBY premiums renew every year from the bank account. Here inertia works for the saver, because doing nothing keeps the person insured or saving.
• NITI Aayog: set up a Behavioural Insights Unit with the Gates Foundation (reported as 2019; its current status has not been verified).

Don't confuse with

• Mandate or ban: a ban removes an option, for example banning junk food. A nudge keeps every option open and only changes how the options are presented.
• Incentive (tax or subsidy): incentives change the price of a choice. A nudge leaves prices largely unchanged. In the pension example, the money stayed the same and only the default changed.
• Sludge: the opposite of a nudge. Sludge adds friction, such as long forms or repeated office visits, that blocks good choices. A nudge makes good choices easier.
• Homo economicus: the fully rational person assumed in classical and neoclassical theory. Nudges are designed for Homo sapiens, real people with biases and habits.

Prelims Hooks

• Nudge (2008) was written by Richard Thaler and Cass Sunstein. Thaler won the Economics Nobel in 2017 for behavioural economics.
• Libertarian paternalism means steering people towards better choices while keeping all options open. A ban is not a nudge.
• Status quo bias is why defaults are powerful. The classic examples are opt-out organ donation (Spain) and pension auto-enrolment.
• The UK's Behavioural Insights Team (the "Nudge Unit") was set up in 2010 under the Cabinet Office and was the first of its kind [10]. The World Bank's WDR 2015 is titled Mind, Society, and Behavior [11], and its eMBeD unit helps governments use behavioural science [12].
• Economic Survey 2018-19, Vol. 1, Ch. 2 set out three principles: social norm, default option, repeated reinforcement [2]. BADLAV = Beti Aapki Dhan Lakshmi Aur Vijay Lakshmi.
• GiveItUp: 1.03 crore LPG subsidy surrenders by 12 December 2018 [5]. Mission LiFE: launched 20 October 2022, P3, 1 billion target for 2022-27 [3][4]. Poshan Maah is held every September [7].

Mains Points

• A low-cost complement to hard tools, not a substitute:
• GiveItUp saved subsidy money without any legal force [5], and auto-debit keeps APY and PMJJBY/PMSBY cover running.

• Nudges alone are not enough. Swachh Bharat needed toilets as well as social norms, so nudges work best alongside laws, subsidies and infrastructure.

• Ethics, accountability and sludge:

• Because nudges work below conscious thought, they raise worries about manipulation and about who defines "better".
• Safeguards include transparency, testing through randomised trials, an easy opt-out and public reporting. The OECD found 202 public bodies applying behavioural insights (2017) [9].

• Cutting sludge is itself a governance reform. Simpler forms, automatic eligibility using data and auto-renewal can raise welfare take-up among the poor and people with little formal schooling.

• Behaviour-led climate and health policy:

• Mission LiFE [4] and POSHAN's Jan Andolan [7] show a move towards mass campaigns that change citizen behaviour.
• Risk 1: responsibility may shift from firms and the state onto individuals.
• Risk 2: counting activities (such as 10.27 crore in 2024) can hide the real results. Success should be judged by outcomes like lower emissions and less stunting.

Related concepts

• Choice architecture
• Default option
• Libertarian paternalism

Read more

• Nudges and behavioural public policy in India