Inequality is shaped not only by who owns what, but also by who belongs where
A society has to answer at least two basic questions.
Who owns what?
And:
Who belongs where?
We usually treat these as different subjects.
Property belongs to economics.
Borders belong to immigration and citizenship.
Thomas Piketty gives us a reason to question that separation.
In the introduction to Capital and Ideology, he writes that every inequality regime rests on both “a theory of borders and a theory of property.”
The property question concerns ownership and economic power.
The border question concerns something different but equally fundamental: who belongs to the political community, who does not, and how political communities relate to one another.
That connection matters for the World Citizen framework.
Inequality is not produced only inside political borders.
Borders themselves help structure people’s opportunities.
Inequality Is Institutional
A central idea in Piketty’s work is that inequality has no single natural or inevitable form.
Societies organize property differently.
They tax wealth differently.
They build different education systems.
They recognize different forms of ownership.
They create different welfare institutions.
And the level and structure of inequality change with those institutions.
Inheritance provides a useful example.
In France, Piketty estimates that the annual flow of inheritance was around 20–25 percent of national income between 1820 and 1910.
By 1950, it had fallen to less than 5 percent.
By 2010, it had risen again to about 15 percent.
That long U-shaped movement is important.
Inheritance did not remain equally important through time.
Its role changed with economic growth, war, taxation, wealth accumulation, and other historical and institutional changes.
The wider lesson is that inequality is not simply something society discovers.
Society helps produce its form.
The Property Question
The property question determines more than who formally owns an asset.
Property institutions influence who accumulates wealth.
Who inherits it.
Who receives income from capital.
Who pays taxes.
Who has access to housing, education, credit, and economic security.
Effort matters.
But effort takes place inside rules that individuals did not choose before entering society.
Property rules are already there.
Inheritance rules are already there.
Tax systems are already there.
Education systems are already there.
Institutions help determine what choices are realistically available.
Borders Are Institutions
Piketty places another institutional question beside the property question: the border question.
Every political system must determine who belongs to the political community and who does not.
That distinction has consequences.
Borders influence who may enter.
Who may work.
Who may remain.
Who may be removed.
Who may vote.
Who may eventually become a political member.
A border therefore does more than divide territory.
Its political meaning is created by law.
A mountain exists whether a legislature recognizes it or not.
A political border is different.
Law determines what crossing it means.
Law determines which documents count.
Law determines whether entry leads to temporary presence, residence, or eventually membership.
This makes the border an institution.
And institutions distribute opportunities.
Two people with similar abilities and ambitions may face very different options because one can enter a political community and the other cannot.
The border does not explain every difference in their lives.
But it can determine which institutional environments are realistically available to them.
That makes borders relevant to inequality.
Inequality Across Political Communities
This connects Piketty with another thinker discussed earlier in this series.
Branko Milanovic has shown how strongly income prospects can be associated with where a person lives.
His work makes the economic importance of location visible.
Piketty approaches the problem differently.
His contribution here is to place the border itself inside the institutional analysis of inequality.
A person may face better opportunities somewhere else.
Whether that person can reach those opportunities depends partly on the border regime.
From the Border Question to Political Freedom
This is where the World Citizen framework takes a further step.
Piketty asks us to recognize that the border question is part of the organization of inequality.
The World Citizen framework asks:
What freedom should individuals have in relation to those borders?
Piketty does not argue for Foot Democracy. That further step belongs to the World Citizen framework.
Foot Democracy concerns the ability to choose among political communities in a meaningful way.
That requires more than a formal right to leave one country.
There must also be meaningful possibilities of Entry elsewhere.
And Entry alone is not enough.
As earlier articles in this series have argued, the relevant path is:
Entry → Residence → Secure Membership → Political Equality
Otherwise a person may cross a border and live for decades under another political system while remaining outside its full political membership.
Borders Can Serve Legitimate Purposes
Recognizing the distributive power of borders does not mean that every restriction is unjust.
Political communities govern collectively.
They maintain institutions.
They finance public services.
They protect rights.
They may face housing constraints, administrative limits, security concerns, fiscal pressures, or sudden concentrations of migration.
Those problems cannot simply be dismissed.
But neither are border restrictions self-justifying.
If borders are institutions with important distributive consequences, restrictions should be open to justification.
What problem is being addressed?
How serious is it?
Is the restriction necessary?
Are less restrictive alternatives available?
Who bears the burden?
And does a temporary difficulty become a permanent exclusion?
These are political questions.
They are not answered merely by pointing to the existence of a border.
Inequality Is Not Only About Redistribution
This changes the way we think about equality.
A society might tax inheritance more heavily.
It might improve public education.
It might expand social insurance.
Those reforms may substantially reduce inequality.
But suppose a person’s opportunities also depend strongly on which political community that person can enter and join.
Redistribution within each state then addresses only part of the institutional structure.
A second question remains:
How should access to political communities themselves be organized?
This does not mean abolishing borders.
It means recognizing that border rules are also rules about opportunity.
Political Freedom Without a Borderless World
The World Citizen framework does not require a world without borders.
Nor does it require a single world government.
Political communities can remain territorial.
They can preserve collective self-government.
Borders can continue to perform important functions.
The question is whether political communities can do this without making full political membership effectively hereditary.
A border regime can regulate Entry without making meaningful Entry impossible.
It can respond to real pressures without converting temporary constraints into permanent exclusion.
It can preserve political communities while allowing people a realistic pathway to become members elsewhere.
That is the institutional challenge.
Conclusion
Thomas Piketty is best known for his work on wealth and inequality.
But Capital and Ideology raises a broader institutional question.
Every inequality regime must answer questions about property.
It must also answer questions about borders.
Who owns what?
Who belongs where?
The two questions are different.
But both help structure the opportunities available to people.
Piketty’s work reminds us that inequality is institutional.
The World Citizen framework adds a further question:
If borders help structure opportunity, what political freedom should individuals have in relation to those borders?
The issue is not whether borders exist.
It is whether the border regime leaves political membership overwhelmingly determined by birth—or gives people a meaningful way to become equal members of another political community.
Notes
Thomas Piketty writes in the introduction to Capital and Ideology that every inequality regime rests on both “a theory of borders and a theory of property.” See Thomas Piketty, Capital and Ideology, trans. Arthur Goldhammer (Belknap Press of Harvard University Press, 2020), Introduction, p. 5.
Piketty later restated the importance of the property and border questions in Thomas Piketty, “Capital and ideology: A global perspective on inequality regimes,” The British Journal of Sociology 72, no. 1 (2021): 139–150.
The French inheritance figures are from Thomas Piketty, “On the Long-Run Evolution of Inheritance: France 1820–2050,” Quarterly Journal of Economics 126 (2011): 1071–1131. Piketty estimates annual inheritance flows at about 20–25 percent of national income between 1820 and 1910, less than 5 percent in 1950, and about 15 percent by 2010.
The extension from Piketty’s border question to Foot Democracy, Migration Freedom, and residence-based political membership is an argument of the World Citizen framework and should not be attributed to Piketty.
Further Reading
For the relationship between location and economic opportunity, see “Branko Milanovic and the Citizenship Premium”.
For citizenship as a form of birthright privilege, see “Ayelet Shachar and the Birthright Lottery.”
For the move from nationality toward residence as the basis of political membership, see “From Nationality to Residence”.
Thomas Piketty, Capital in the Twenty-First Century (Harvard University Press, 2014).
Thomas Piketty, Capital and Ideology, trans. Arthur Goldhammer (Belknap Press of Harvard University Press, 2020; French original, 2019).
Thomas Piketty, A Brief History of Equality, trans. Steven Rendall (Belknap Press of Harvard University Press, 2022).
Thomas Piketty and Michael J. Sandel, Equality: What It Means and Why It Matters (Polity, 2025).
