Why entropy, not energy?

发表时间：2026-06-16 08:22

In our daily life, we use the concept of energy a lot. We rarely, if ever, use the concept of entropy. Therefore, a realistic theory of economics should be based energy, not entropy. Right?

Energy is so important to our society. Many people have devoted their lives to improve the efficiency of energy use. One of them is Sadi Carnot, often called “the father of thermodynamics”. We will use an analogy to understand his idea.

Imagine we stay in an environment of 15 degree centigrade, or 25 degree, 35 degree, 45 degree. When we are in an environment of 15 degree and exercise actively, we may find our exercise go on effectively. When we are in an environment of 25 degree and exercise lightly, we feel well. But if we exercise actively, we may feel hot and tired soon. When we are in an environment of 35 degree, we feel hot even without exercising. When we are in an environment of 45 degree for a prolonged period, we will feel extremely uncomfortable. (Sauna room is much hotter than 45 degree. It is very dry. We can sweat profusely to lose heat. Steam room, which has 100% humidity, is about 45 degree. We can’t lose heat from sweating in a steam room. 45 degree feels extremely hot.)

From the above discussion, our effectiveness in exerting energy depends not only on our own energy level, but also on the environment. In general, Sadi Carnot found, the maximum efficiency of an engine in transforming energy into mechanical work is (T2 - T1)/T2. Here T2 is the temperature of the engine chamber and T1 is the temperature of the environment. The level of efficiency is always less than one. If the environmental temperature is the same as the temperature of the engine’s chamber, no useful energy can be exported.

If you find the above discussion too abstract, just imagine yourself in an environment of 37 degrees. You may find yourself quite sluggish and unwilling to do heavy work. You can still do some work. This is because your body depends on other types of differentials, chemical differentials and electrical differentials, not just temperature differentials. You can also lose heat by sweating.

Overall, your ability to do work, or a machine’s ability to do work, depends not only on your energy level, but also on the energy level of the environment. (Heat is thermal energy.) A large amount of cold water and a small amount of hot water may contain the same amount of energy. But the amount of work they can perform is different. A large number of untrained civilians may have the same muscle energy as a smaller number of trained soldiers. But the fighting powers of two groups are very different, even when the soldiers are unarmed. If we use energy to describe a physical system, which includes economic system, we may not get accurate results. People start to search for a more accurate way to describe a system’s ability to perform useful tasks. Rudolf Clausius found the concept of entropy.

The concept of entropy, at its core, is very simple. Entropy is simply probability. Suppose all air molecules are at half of a chamber. The probability of air filling the whole chamber is much higher. Hence there is a strong tendency for air to fill the whole chamber. If you put an engine at a hole from the separation between two halves of the chamber, the movement of air molecules will drive the engine to produce useful work. In general, when a system moves from low probability state to a high probability state, useful work can be done. The number of possible states is defined as entropy. In formal language, a system has a tendency to move from low entropy state to a high entropy state. Useful work can be done in the process. It is that simple!

If the concept of entropy is so simple, why people have such a difficulty understanding it? It is because humans don’t think in this way. When people drive EV, they think they are saving the world. From the entropy theory, you have to include all processes. The production of battery is highly polluting. If you tell Tesla drivers or shareholders this fact, they will not appreciate it. They will be very angry. Entropy adds up all parties. But people only care about selective parties. The concept of entropy makes it difficult to ignore other parties. This is one reason why people don’t like to apply the concept of entropy to specific problems, such as economic problems. People do talk about entropy in nonsenses, to show off their sophistication.

From the standard physics, energy is conserved. A conserved quantity doesn’t drive anything. It is fine to use the term energy in our daily conversation. But we won’t go far when we use energy in formal analysis. This is like we talk about sun. In our daily conversation, we say sun rise, sun set. But if physicists consider the sun move around the earth, their analysis won’t go far. Some ancient Greeks already knew the earth moved around the sun. But it took about two thousand more years for the mainstream to accept the idea.

Entropy is a more accurate measure of what drives the world. But it reveals too much what people don’t want to see. When you play an iPhone, you think you are dematerializing the materialistic society and hence doing the noble work. You don’t want to hear an iPhone, or any high tech gadgets, requires tremendous amount of material input. An iPhone is cheap only because people in the supply chain work like slaves. People like to display the coffee they drink are ethically sourced. If high tech gadgets are ethically sourced, few can afford them. A truly accurate measure makes most people uncomfortable. That is why humans resist the concept of entropy.

If so, why entropy becomes widely adopted in physics? This is like the concept of the sun centered solar system. If we insist the earth is the center of the universe, much of physics cannot be developed. The concept of entropy is tremendously useful in physics, chemistry and biology.

The concept of entropy will be extremely useful for most people in the world as well. When we apply the entropy theory of value, we will realize most policies advocated by the mainstream institutions harm ordinary people. DEI is such an example. If DEI is such a wonderful idea, why is it only been applied to ordinary people, not to the elite? In fact, the inequality level has been increasing since DEI has become fashionable. With the help of the entropy theory of value, we can easily recognize DEI as a type of divide and rule, which has been practiced by the ruling class for a long time. While the concept of entropy threatens the ruling class by exposing their deception, it will empower the masses with truth.