my theory of the industrial revolution

Link post

Why did the Industrial Revolution happen when it did? Why didn’t it happen earlier, or in China or India? What were the key factors that weren’t present elsewhere?

I have a theory about that which I haven’t seen before, so I thought I’d post it.

steam power

One popular conception of the Industrial Revolution is that steam engines were invented, and then an increase in available power led to economic growth.

This doesn’t make sense, because water power and horses were much more significant than steam power until well after technological development and economic growth became fast. (Also, steam engine designs wouldn’t have caused economic growth in Ancient Rome because manufacturing them wasn’t practical at the time.) Steam power being the key factor is now considered a discredited view by most historians.


Agricultural productivity in Europe improved significantly before the Industrial Revolution, and rapidly during it. Improvements included:

  • plant selective breeding

  • 4-field crop rotation

  • heavy ploughs

  • horse breeding

  • threshing machines

  • roller mills

This reduced the number of farmers needed, potentially allowing more people to do research, or other kinds of work with more available technological improvement.

More people doing research can certainly make it go faster, but there were already intellectuals and a leisure class before the Industrial Revolution. The increase in tech development was disproportionate to the non-farmer population. The UK population also increased, but it was still a relatively small fraction of the world population, and most of its population growth happened after 1800.


Britain made a large canal system that enabled funneling food to London. Combined with agricultural progress, this enables a large city, and London was the largest city in the world starting in around 1830.

But by 1830, the Industrial Revolution was already well underway. There were already large cities such as Beijing well before that point, so “a large city” was not the only key factor.

my theory

My view is that the Industrial Revolution happened due to the combination of:

  • a large city

  • European culture

  • printing presses with movable type

  • a positional number system with zero

  • English spelling reform


If you look at the inventions of ancient China and ancient Mesopotamia, I think there was less emphasis on practicality and usage by the common people. For example, al-Jazari largely made toys for the wealthy, and Zhang Heng made tools for astrology.

Europe had a long history of continuous warfare, and unskilled labor was less available than in China. I think that led to a greater emphasis on practicality of inventions.

intellectual tools

The Gutenberg Press was invented around 1440. That made it possible to spread written works much more widely and with fewer mistakes, making communication faster and reducing the chance that progress would be lost.

Fibonacci brought Arabic numerals to Europe around 1200, but they remained rare until after 1450. Between 1470 and 1550, they were spread rapidly by the printing press. Engineering requires multiplication, and multiplication is much easier with Arabic numerals than Roman numerals. That change made calculations faster and reduced their error rates.

The introduction of the printing press also drove standardization of English spelling. Originally, written English words didn’t directly represent meanings; rather, sounds/​pronunciations were linked to meanings, and different people had various ways of representing those pronunciations with letters. That spelling standardization reduced the chances of misreading words and made reading faster.

error rates and exponentials

Consider a model where knowledge (K) accumulates or decays exponentially over time, and is also developed with diminishing returns, such as:

  • K’/​time’ = a*K + b*K^c (c < 0)

If (a, b, c) are such that the exponent of knowledge accumulation is positive for smart individuals but negative for interpersonal communication in a society, then K reaches an equilibrium value, with occasional peaks from a rare genius or intellectual society, but that progress later decaying due to imperfect communication and preservation.

The printing press made intellectual work less likely to be lost. Arabic numerals made calculation errors less likely. Spelling standardization made misreading text less likely. My theory of the Industrial Revolution is that those factors collectively reduced the decay of knowledge enough that the exponent for societal-level knowledge growth went significantly positive up to much higher levels of intellectual progress.

Then, knowledge accumulated exponentially in the UK from 1500 to 1800. This led to agricultural productivity increasing from around 1525, and eventually to the accumulation of enough societal knowledge for the Industrial Revolution.