What Do We Owe Strangers? A Guide to Cosmopolitanism
Imagine you’re walking home from school and you see a kid your age sitting on a bench, crying. You don’t know them. They go to a different school. You’ll probably never see them again. Do you have any obligation to stop and help?
Most people would say yes—or at least feel that they should help. Now imagine that instead of one kid, there are a million kids just like that one, living in another country, starving. You could send ten dollars right now on your phone and it would actually help. Do you have to? Is it just a nice thing to do, or is it a duty?
This is the question at the heart of an old and strange idea called cosmopolitanism. The word comes from Greek: kosmos (world) and polites (citizen). A cosmopolitan is someone who calls themselves a “citizen of the world.” But what does that actually mean? Does it mean you have to treat everyone exactly the same? Does it mean you shouldn’t love your own country or your own family more than anyone else’s? Philosophers have been arguing about this for over two thousand years.
The Original World Citizen
The first person to call himself a “citizen of the world” was a weird, eccentric philosopher named Diogenes (around 400 BCE). He lived in Athens but he wasn’t from there—he was from a place called Sinope, in what’s now Turkey. When people asked him where he came from, he didn’t say “Sinope.” He said, “I am a citizen of the world.”
At the time, this was a shocking thing to say. In ancient Greece, your identity was all about which city you belonged to. You fought for your city, you worshipped its gods, you owed it your loyalty. Saying you were a citizen of the world was like saying you didn’t owe any particular city anything—that your allegiance was to everyone, everywhere.
But here’s the tricky part: nobody is entirely sure what Diogenes meant by this. He seems to have been making a negative claim—rejecting the idea that he owed special loyalty to Sinope just because he was born there. But did he have any positive ideas about what world citizenship required? Did he think people should work to create a world government? We don’t really know. He was famous for living like a dog (the word “cynic” comes from the Greek word for dog), sleeping in a barrel, and generally rejecting all social conventions. It’s possible his cosmopolitanism was just another way of saying: “I don’t play by your rules.”
The Stoics Take It Further
A few generations later, a school of philosophers called the Stoics picked up the idea and ran with it. They had a beautiful vision: the entire universe (the cosmos) is like a single city, governed by a single law—the law of reason. And every human being, by virtue of having reason, is a citizen of this world-city.
What does this mean practically? The Stoics thought it meant you should try to help all human beings, not just the ones from your own city. But they were also realists. They knew you couldn’t help everyone equally. You can’t be best friends with a billion people. So what do you do?
The Stoic answer was: you figure out where you can do the most good, and you do that. Sometimes that might mean staying in your own city and helping your neighbors. Sometimes it might mean moving somewhere else because you’re needed more there. What matters is that you’re not limited by patriotism—you don’t say “I’ll only help Athenians” because you were born in Athens. You look at the whole world and ask: where can I serve best?
The Roman Stoics added something important: they said all human beings are citizens of the world, not just the wise and virtuous ones. This was a big shift. For earlier Stoics, you had to actually be a good person to count as a world citizen. The Romans extended citizenship to everyone, simply because they had reason. That’s a much more inclusive vision—and it’s one that has echoes in modern ideas about universal human rights.
Two Big Questions
Cosmopolitanism today comes in many flavors, but most of them are trying to answer two questions:
First: what do we owe strangers? This is the moral question. If I have a duty to help people in need, does it matter whether they’re my classmates or kids on the other side of the planet? Some cosmopolitans (called strict cosmopolitans) say no—distance and nationality make no difference. If a kid in my neighborhood is hungry, I should help. If a kid in another country is equally hungry, I should help equally. Other cosmopolitans (called moderate cosmopolitans) say that while we do have duties to everyone, we also have extra duties to people we’re close to—our family, our friends, our fellow citizens. Both groups agree we have duties to strangers. They disagree about how strong those duties are.
Second: should there be a world government? This is the political question. If we’re all citizens of the world, should there be actual world-wide political institutions? Should there be a global parliament? A world court? An army that can enforce international law?
The answers range from “yes, absolutely” to “no, that’s a terrible idea.” Some philosophers (like Anacharsis Cloots, writing during the French Revolution) argued that all existing countries should be abolished and replaced with one world state. Others (like Immanuel Kant) argued for a looser “league of nations” that would keep peace between countries without overriding their sovereignty. And still others argue that we should focus on layered sovereignty—having many different levels of government (local, regional, national, global), each with limited powers, rather than one big world state.
What Could Possibly Go Wrong?
If you’re a smart 12-year-old reading this, you’ve probably already thought of some objections. Here are a few that philosophers have raised.
Objection 1: You Can’t Love Everyone
The philosopher Jean-Jacques Rousseau complained that cosmopolitans “boast that they love everyone, to have the right to love no one.” In other words: if you spread your caring too thin, you end up caring about nobody at all. Real love and loyalty require particular attachments—to your family, your friends, your country. Without those attachments, you’re just a cold, rootless person who belongs nowhere.
The cosmopolitan’s reply: we’re not asking you to stop loving your family. We’re asking you to expand your circle of concern. You can love your mom and care about strangers in another country. They’re not in competition. In fact, some cosmopolitans argue that the ability to care about people far away is a natural extension of the ability to care about people close to you—starting with your caregivers and rippling outward to include ever-wider circles.
Objection 2: It’s Impossible Anyway
Another objection says: look, it’s nice to dream about world citizenship, but it’s not going to happen. People will never feel that attached to humanity as a whole. Nationalism is too powerful. And even if you could set up a world government, it would probably become a terrifying global dictatorship with no way to escape.
The cosmopolitan might reply that history shows human loyalties are surprisingly flexible. People used to feel intense loyalty to their village or tribe, and now they feel loyalty to countries with hundreds of millions of people—countries that didn’t even exist a few hundred years ago. Why couldn’t that process continue? As for the dictatorship worry, many cosmopolitans argue for limited global institutions, not a total world state. The European Union, for example, is a real-world experiment in sharing sovereignty without creating a super-dictator.
Objection 3: You Owe Your Fellow Citizens More
A third objection is more subtle. It says: even if you have duties to strangers, you have extra duties to your fellow citizens, because they’re the ones who provided you with benefits (roads, schools, police protection), because you implicitly agreed to be part of their society, or because citizenship is a special relationship (like friendship) that comes with its own obligations.
The cosmopolitan has several replies. First, the benefits you receive from your fellow citizens are mostly provided by the state, not by individuals—and the state doesn’t need your personal charity to function. Second, it’s not clear you agreed to anything by being born somewhere. And third, even if citizenship is a special relationship, you can still have universal duties on top of your special ones.
The Debate Today
Cosmopolitanism isn’t just an old idea from ancient Greece. It’s alive and well in philosophy departments, but also in real-world debates.
When people argue about whether rich countries should accept refugees, they’re engaging with cosmopolitan questions. When activists demand that corporations stop using sweatshop labor in poor countries, they’re acting on cosmopolitan principles. When the United Nations writes a Universal Declaration of Human Rights, it’s making a cosmopolitan claim: that every human being, anywhere on earth, has certain basic rights just because they’re human.
At the same time, critics worry that cosmopolitanism can be used to justify bad things. Some European colonizers in the 18th and 19th centuries claimed they were “civilizing” the rest of the world—a kind of fake cosmopolitanism that was really about conquest and exploitation. And some modern economists argue for a global free market in the name of cosmopolitanism, but critics say this just enriches the rich and leaves the poor with nothing.
So the debate is still very much alive. Nobody has settled it. And as the world gets smaller—as we’re more connected to people in other countries than ever before—the questions cosmopolitans ask only become more urgent.
What Do You Think?
Here’s where things get interesting. You don’t have to be a philosopher to think about these questions. You encounter them every day. When you see a fundraiser for kids in another country, do you feel the same tug as when you see a fundraiser for kids in your own school? Should you? When you hear someone say “America first” or “our country matters more,” what do you make of that? Is patriotism a virtue, or is it just prejudice by another name?
The cosmopolitan says: every human being matters, and distance doesn’t change that. Your loyalty should be to humanity, not to an accident of birth.
But is that really possible? And would a world of cosmopolitans even be a good one? Maybe we need the warmth of belonging, the particular love of our own people, to be fully human. Or maybe that’s just an excuse for selfishness.
There’s no easy answer. Which is exactly what makes it philosophy.
Key Terms
| Term | What it does in this debate |
|---|---|
| Cosmopolitanism | The view that all human beings belong to a single community, and that this community matters for how we should live and what we owe each other |
| Strict cosmopolitan | Someone who says distance and nationality make no difference to our moral duties—we should help strangers as much as we help neighbors |
| Moderate cosmopolitan | Someone who says we have duties to everyone plus extra duties to people close to us (family, friends, fellow citizens) |
| World state | A single government covering the entire planet, which some cosmopolitans want and others think is a bad idea |
| Sovereignty | The idea that a country has the right to govern itself without interference from other countries |
| League of nations | A voluntary association of independent countries that cooperate on certain issues, without any single country giving up its sovereignty |
Key People
- Diogenes of Sinope (c. 400–323 BCE) – A Greek philosopher who lived in a barrel and called himself “a citizen of the world,” probably meaning he rejected loyalty to any particular city.
- The Stoics (3rd century BCE onward) – A school of philosophers who argued that the universe is like a single city governed by reason, and that all rational beings are its citizens.
- Immanuel Kant (1724–1804) – A German philosopher who argued for a “league of nations” to keep peace and introduced the idea of “cosmopolitan law”—rights that individuals have as citizens of the earth.
- Anacharsis Cloots (1755–1794) – A French revolutionary who argued for a single world state and was executed during the Reign of Terror.
- Jean-Jacques Rousseau (1712–1778) – A philosopher who criticized cosmopolitans for pretending to love everyone so they could avoid loving anyone in particular.
Things to Think About
- If you had to choose between saving ten strangers in another country or one close friend, which would you save? Does your answer tell you anything about what you really believe about duties to strangers?
- Imagine a world where everybody truly felt like a citizen of the world—where national borders meant nothing emotionally. What would be gained? What would be lost?
- The Stoics said all humans are part of one community because we all share reason. But do you think all humans always act reasonably? What about people who do terrible things—are they still part of the world community? Should they be?
- Cosmopolitanism is often associated with wealthy, educated people who can afford to travel and feel “at home everywhere.” Is there a danger that cosmopolitanism becomes just another privilege of the rich?
Where This Shows Up
- Refugee and immigration debates – Arguments about whether countries have a duty to accept people fleeing war or poverty are directly about cosmopolitan vs. nationalist ideas.
- Human rights organizations – Groups like Amnesty International and the Red Cross act on the cosmopolitan assumption that all humans deserve basic rights, regardless of nationality.
- Global climate change – If carbon emissions from one country affect the whole planet, cosmopolitanism says every country has a duty to care about the effects elsewhere.
- The United Nations – Its very existence is a cosmopolitan experiment: an attempt to create international institutions that serve all of humanity, not just individual countries.
- Online fundraising – When you see a GoFundMe for someone you’ll never meet on the other side of the world, and you feel like you should help—that’s the cosmopolitan impulse, right there.