Often times people ask (even here on HN) whether the Romans could have built steam engines. Here's my theory: yes, absolutely. Technologies evolve for either

Often times people ask (even here on HN) whether the Romans could have built steam engines. Here's my theory: yes, absolutely. Technologies evolve for either military use or non-military use. Military technologies are subject to evolutionary pressures that are easily 100 to 1000 times higher than non-military technologies. An iron plow will do a better job than a wooden plow, but in the end it's just a matter of slightly increased productivity. But an iron sword vs a wooden alternative, that's life and death. Military technologies, throughout ages, evolved many times faster than civilian ones. Do you think the technology to make an iron sword is harder, or simpler than the technology to distill spirits? Obviously harder, maybe 100 times so. Yet, swords appeared 5000 years ago, spirits about 1000 years ago. The Romans developed a huge industrial base capable of churning hundreds of thousands of "lorica segmentata" armors, yet, their technology when it came to textile dyes was absolutely pathetic. Etc, etc. My point is the steam engine emerged as a civilian technology, not a military one. Once it matured, it powered battleships, so it obviously acquired a military relevance, but in the times of Watt, it was definitely civilian. But could we have lived in an alternate history where the steam engine appeared as a military technology? If so, then it could have evolved many times faster, and I contend that I can see a scenario where the Romans (well, the Eastern Roman empire) could have initiated an industrial revolution. Centered around oil (petroleum), not coal. Hint: they possessed the Greek fire, a fundamental military technology. For some reason the Greek fire disappeared, and history evolved fire weapons starting with cannons. But it's entirely reasonable to think the fire weapons evolved out of Greek fire (i.e. flamethrowers), and this would have stimulated a healthy trade in petroleum, 1000 years before the real history.