Economic equilibrium

Buying and selling can find a balance.

Sellers make things to sell. Buyers want to buy those things. A fair price helps both sides.

When the price is right, everything stays steady. The amount made is the same as the amount wanted.

If the price is too high, there is too much to sell. If the price is too low, there is not enough.

Prices can change if people want things differently. This helps the market find a new balance.

In economics, a balance can happen in a market. This is called economic equilibrium. It occurs when supply and demand are even. Supply is the amount of goods sellers make. Demand is the amount buyers want to buy.

At this balance, the price stays steady. This is the market clearing price. At this price, the amount made equals the amount wanted.

If the price is too high, sellers have too much. This is called excess supply. This extra supply can push prices down. If the price is too low, there is a shortage. This shortage can push prices up. These changes help the market find its balance again.

Sometimes, one company has a monopoly. A monopoly is when one seller controls the market. In this case, the balance might be different. The seller may keep the supply low to keep prices high.

Other thinkers look at how companies act together. Antoine Augustin Cournot studied this in 1838. He looked at how two firms make choices. This can lead to a Nash equilibrium. This is a state where no firm wants to change its plan.

Economic equilibrium is a special state of balance in a market. It happens when the forces of supply and demand match perfectly. Supply is the amount of goods that sellers provide. Demand is how much those goods are wanted by buyers.

When these two forces are equal, the market reaches a steady point. This point is often called the market clearing price. At this price, the amount produced equals the amount people want to buy. This means the price and the amount of goods will not change. This stability continues unless something new changes the supply or the demand.

Experts use certain rules to describe how this balance works. A thinker named Huw Dixon proposed three main properties of equilibrium. First, the behavior of all people in the market must be consistent. Second, no one should have a reason to change what they are doing. This means buyers do not want to buy more or less. It also means sellers do not want to sell more or less.

Third, equilibrium should be the result of a moving process. This is called stability. If the price is too high, sellers have too much stuff. This extra supply pushes the price back down toward the balance point. If the price is too low, there is a shortage. This shortage pushes the price back up to find the sweet spot.

History shows us different ways that markets find their balance. In 1838, Antoine Augustin Cournot studied how two companies act together. He looked at a situation called a Cournot duopoly. In this setup, two firms make choices based on what the other firm does. This can lead to a Nash equilibrium. This is a state where neither firm wants to change its plan.

They both choose the best amount to produce to make the most profit. This idea is very different from a simple market with many sellers. It shows how people must think about the choices of others to find a balance.

Sometimes, a single company can control a whole market. This is called a monopoly. In a monopoly, the balance works differently than in a normal market. The company wants to make the most profit possible. They might keep the amount of goods low to keep the price high. This means the amount buyers want and the amount sellers provide are not equal. While the company is happy with its profit, the buyers might want more. This shows that a market can be in balance even if it is not perfect for everyone.

It is important to remember that a market balance is not always fair. A market can be in equilibrium even when people are suffering. For example, during the Great Famine in Ireland from 1845 to 1852, food was exported to England. The price of potatoes was high enough for profit, but too high for Irish farmers. This meant the market was in balance, but many people went hungry.

Economists like Paul Samuelson warn us about this. A steady price does not always mean the situation is good for every person.

Economic equilibrium is a state of balance in an economy. It occurs when the forces of supply and demand are perfectly matched. In this state, economic variables like price and quantity stop changing. This balance is often called the market clearing price. At this price, the amount of goods sellers provide equals the amount buyers want. This concept was borrowed from the physical sciences. In physics, a system is in equilibrium when physical forces are balanced. In economics, this means no further changes happen unless something external shifts the market.

To understand how this works, we can look at three specific properties. Economist Huw Dixon proposed these three rules to describe equilibrium. The first property, P1, is consistency. This means the behavior of all agents in the market is consistent with the price. The second property, P2, is incentive. This means no single person or company has a reason to change their strategy. If they tried to change, they would not improve their own situation. The third property, P3, is stability. This means the equilibrium is the result of a dynamic process that brings the market back to balance.

In a competitive equilibrium, these properties work together. At the equilibrium price, the quantity supplied equals the quantity demanded. Buyers choose amounts to maximize their utility, which is their satisfaction. Sellers choose amounts to maximize their profits. Because both sides are satisfied, no one has an incentive to change. We can see stability by looking at what happens when the price is wrong. If the price is too high, there is an excess supply. This extra stock puts downward pressure on the price. If the price is too low, a shortage occurs. This shortage pushes the price back up toward the equilibrium.

Not all markets behave this way, such as in a monopoly. A monopoly is when one company controls the entire market. In this case, the company sets its production where marginal revenue equals marginal cost. Marginal revenue is the extra money earned from selling one more unit. Marginal cost is the extra cost of producing that unit. In a monopoly, the equilibrium does not satisfy property P1. This is because the amount demanded by consumers is not equal to the amount supplied by the firm. Consumers actually have an incentive to demand more at the market price. However, the monopolist has no incentive to change because they are already maximizing profit.

Another important type of balance is the Nash equilibrium. This concept is used when companies must think about each other's moves. It was first used by Antoine Augustin Cournot in his 1838 book. He studied a Cournot duopoly, where two firms compete in the same market. In this model, each firm chooses its output based on what the other firm does. This is called strategic interdependence. The Nash equilibrium occurs when both firms choose the best possible output for themselves, given the output of their competitor.

Finding the exact equilibrium price requires specific mathematical tools. Economists often plot supply and demand curves on a graph. The point where these two lines intersect is the equilibrium.

At this intersection, the quantity demanded and the quantity supplied are identical. If the price moves away from this point, the market forces of surplus or shortage will pull it back. This automatic correction is a key difference between free markets and central planning. In central planning, governments try to set prices, which often leads to persistent shortages.

It is vital to remember that equilibrium does not always mean a situation is fair. Economists like Paul Samuelson warn that a market can be in balance even during a crisis. A famous and tragic example is the Great Famine in Ireland from 1845 to 1852. During this time, food was exported to England because it was more profitable. The equilibrium price for potatoes was high enough for profit, but too high for Irish farmers to afford. This meant the market was in a steady state, even though many people were starving. Equilibrium describes how a system balances, not how a system treats people.