Ellsberg Paradox

What is the Ellsberg Paradox?

Have you ever had to make a choice, but felt unsure because you didn’t have all the information? That’s a bit like what the Ellsberg Paradox is all about. In simple terms, the Ellsberg Paradox is a puzzle from the world of economics that shows how people behave differently when they don’t know all the risks. Imagine you’re choosing between two mystery boxes – one has a surprise that could be good or bad, and the other has a surprise, but you have no clue what the odds are. Many people would avoid the complete mystery, even if both choices could give the same reward. This paradox is like a big question mark in how we predict decisions in economics because it goes against the idea that we always make super logical choices.

Another way to look at the Ellsberg Paradox is to think about it as uncovering a quirk in how we make choices. When the risks are clear, we can be pretty good at weighing our options. But when things get fuzzy and we’re not sure about the risks, we often choose to stay away from what’s uncertain. Just like if you had to choose between a quiz you’ve studied for and a pop quiz on any subject, you might feel better about the one you’ve prepared for. That’s a bit like the Ellsberg Paradox at work in everyday life.


The thought puzzle that is the Ellsberg Paradox was thought up by a smart guy named Daniel Ellsberg back in 1961. He wanted to understand why people might make choices that seem odd when they’re not sure what might happen. By creating a simple game with balls of different colors, he showed that people didn’t act the way economists thought they should when they didn’t know all the odds.

Key Arguments

  • People often choose a risk they know over one they don’t, even if the mystery risk could be the same.
  • The usual way we think people make decisions about risk doesn’t always line up with what they actually do, because it assumes everyone’s super logical about unknowns.
  • Real-life choices show us that something else is going on when the risks aren’t clear, and this something else is our tendency to shy away from what we can’t predict.
  • This paradox highlights that avoiding risk is a powerful force in our decisions, one that can twist the expected value of a choice based on how much we do or don’t know.

Answer or Resolution

There’s no easy answer to the puzzle of the Ellsberg Paradox. But smart people have come up with ideas like prospect theory that try to explain why we might choose to dodge uncertainty. This idea sees our decisions as more of a dance with potential wins and losses that aren’t always balanced. It also brings in the concept of not liking ambiguity as a key player in how we make choices.

Major Criticism

Some say that the Ellsberg Paradox isn’t really showing that choices are irrational; instead, it might just mean we need to think about what ‘rational’ really means when it comes to uncertain situations. Others are a bit careful about taking the lessons from the paradox too far since real life can be a lot messier than picking colored balls out of an urn.

Practical Applications

The Ellsberg Paradox isn’t just for economists to ponder — it has useful roles in everyday life and various areas:

  • Economics: It makes us rethink how we see risk and uncertainty, which is super important for things like insurance, trading money, and figuring out market trends.
  • Psychology: It helps us understand why people think the way they do, especially the shortcuts and mistakes our brains make.
  • Political Science: Knowing about the Ellsberg Paradox can shine a light on how leaders make tough calls when they don’t have all the intel.
  • Business: Companies can use this insight to better plan for the future, considering how people handle not knowing all the facts.

Explaining the Ellsberg Paradox

  • Imagine an urn with 90 balls: 30 are red and the rest are black or yellow, but you don’t know how many of each.
  • Would you bet on a red one or a black one being pulled out? Most folks would bet on red because they know exactly what their chances are.
  • How about choosing to bet on either a red or yellow one, or on a black or yellow one? Even though the odds are the same, most people now switch to pick black or yellow.
  • This flip-flop in choices doesn’t make sense on paper, but it happens because we’re not comfortable not knowing the chances of pulling a black versus a yellow ball.

This simple game is a really good way to see the Ellsberg Paradox in action. Even though our logic should tell us the odds haven’t changed, our gut makes us favor the choice where the risk is clear over the one that’s all foggy.

Related Topics

  • Prospect Theory: A theory that helps explain why we might take a guaranteed small reward over a gamble with a larger one, because losing feels worse than winning feels good.
  • Behavioral Economics: A field that blends psychology with economics to understand how actual people, rather than perfectly logical beings, make economic decisions.
  • Risk Aversion: A general preference to avoid losses over acquiring gains. It’s why people might choose a stable job over the chance of a higher-paying but less secure one.
  • Decision-making under Uncertainty: This involves making choices without having all the information, which includes pretty much every big decision in life, from where to go to college to what to buy with your savings.


The Ellsberg Paradox is more than just an interesting conundrum in economics; it gives us a window into how messy and complex our choices can be when we’re not sure about the outcomes. It encourages us to think twice about how people tackle unknowns and has pushed for new theories that better fit how we actually behave. In the end, the paradox shines a light on the fact that when faced with the unknown, we’re not always the cool, calculated decision-makers we might like to think we are.