Can the rise and fall of civilizations be explained through first principles in historical research?

Of course, we can talk about it; this is a very interesting question.

We can imagine a civilization as an incredibly complex game or a giant company. Now you want to know whether the players in this game, or this company, will ultimately succeed or fail.

The term "first principles" sounds profound, but in essence, it's a way of thinking that involves "getting to the root of things." It doesn't care how others play, nor does it concern itself with past success stories. Instead, it directly asks: "What are the most fundamental rules of this game?" It's like playing with building blocks: instead of thinking, "How do I build a castle just like someone else's?" you first consider, "What shape are the blocks? How much force can they withstand? How can they be combined most stably?"

So, can this approach explain the rise and fall of civilizations?

To some extent, yes, and it can help us see many fundamental issues.

Regardless of its brilliant culture or complex institutions, every civilization relies on a few basic "underlying rules":

1. Energy: This is the most fundamental. Any civilization must have enough energy to sustain itself. For ancient civilizations, the primary energy source was food. If a civilization cannot produce or acquire enough food to feed its population, everything else is moot. Therefore, agricultural technology, soil fertility, and climate change—factors that directly affect "energy input"—are the cornerstones determining a civilization's fate. It's like your phone; if it runs out of battery, no matter how many features it has, it's useless.

2. Resources and Environment: Besides food, civilizations need various resources like water, timber, and minerals. At the same time, they must be able to manage their own waste and pollution. Many civilizations declined directly because they depleted local resources (like forests, water sources) and the environment was damaged to the point where it could no longer support so many people. This is a hard constraint that cannot be circumvented.

3. Security: This includes two aspects: external and internal. Externally, there must be the ability to resist enemy invasions; internally, there must be order, not constant civil strife, and people must have a basic sense of security. If a civilization is geographically exposed on all sides, or if it's plagued by internal conflicts, it's like a leaky bucket that will eventually run dry.

4. Population: People are the carriers of civilization. Too few people prevent complex social division of labor; too many people, exceeding the carrying capacity of energy and resources, will lead to famine and unrest. Maintaining a healthy, vibrant, and moderate population size is also an underlying rule.

From these perspectives, when you examine the rise and fall of many empires, the narrative becomes much clearer. For example, in the late Roman Empire, land concentration was severe, small farmers went bankrupt, and food supply issues arose (energy); internal politics were chaotic, with constant civil wars (security); and it was ultimately brought down by external "barbarian" invasions. You see, all these fundamental pillars were compromised.

However, this method also has significant limitations.

Why can't it explain everything? Because civilization is not a purely physical system; it is composed of "people" with thoughts and emotions. This introduces several variables that first principles struggle to handle:

1. Thought and Culture: This is like the "software system" of a civilization. A new religion, a revolutionary philosophical idea, a strong sense of national identity—these things have immense influence, but you can hardly quantify them, let alone derive them from physical aspects like "energy" or "resources." For instance, the rise of Christianity changed the late Roman Empire, and Confucian thought shaped Chinese civilization for thousands of years. The power of this "software" can sometimes even transcend the limitations of "hardware."

2. Contingency: History is full of "black swan" events. A sudden plague (like the Black Death) could severely weaken a flourishing civilization; a brilliant military strategist or an incompetent emperor could completely alter a nation's destiny in just a few decades. These contingent factors are like a god-tier boss or a fatal bug that suddenly appears in a game; they don't follow conventional "underlying logic."

3. Human Agency: People are not simple cogs. Faced with a crisis, some choose to give up, some choose to reform, and some choose to take extreme risks. A great reformer, a disruptive technological invention (like printing or gunpowder), can "change fate against all odds" at a critical moment. This creativity and uncertainty are unpredictable by first principles.

So, what's the conclusion?

Using first principles to analyze history is a very powerful "thinking tool," but it is not a "universal formula" that can provide standard answers.

It can help you cut through the fog of history, grasp the most core and fundamental contradictions, and prevent you from being misled by the personal deeds of kings and generals or the intrigues of the court, allowing you to see the true "basic foundation" of a civilization's survival.

But you must also understand that history is a vast web woven by physical laws, biological instincts, and human thought, full of contingencies. First principles can help you clarify some of the broadest warp and weft threads, but they cannot tell you how every knot in the web was tied, or how a butterfly effect might unleash a storm.