My issue with these projections is that they're so wildly ambitious yet so vague.

What does "mastering AI" look like to you? Do you mean "mastering the generative language/image/video models we have today?" Are you expecting further massive leaps in capabilities and mean to refer specifically to people who master those? You compare it to knights and horses, yet "hard power" technologies like that have obvious aspects that today's "AI mastery" doesn't. (As an aside, I lose track of your telling of history, it seems like you're saying knights replaced Roman Legions but also that they made civilian militaries obsolete, but you also say those legions were "expert and well paid soldiers" already?)

I'd also expect a lot of things to be more "reinforcing" effects vs "generating" effects. Trump, for instance, was already famous as both a big businessman and a television personality; lots of other people "merely" mastered social media and "only" got a bunch of money for it. Could Trump have become President before Twitter? Reagan did it... it took a slightly different path back then, but being famous is a REALLY BIG starting point.

I do not know what mastering AI looks like, revolutionary technologies like these can't be predicted that far into the future. But it definitely does not look like 'banning AI'.

The advantage of the knight, over the legionnaire. Was that one knight could crush 20 legionnaires (with support from peasants), yet supporting one knight costed far far less than 20 legionnaires. That's a military productivity advantage. The expertise and training of the legions were nothing in front of the full might of the warhorse.

Legions were 'trained', but its an on-the-job training, rather than something you aim for since 5 years old. Legions are recruited from civilians, knights usually inherited. All these social changes, because of the horse.

The printing press and the gun combined, cause the inverse effect. Bureaucracies became radically more efficient with cheap printed paper, and guns meant that a soldier trained for one year, could fight against knights trained for decades. Which lead to centralized empires, decline of the knights, and eventually the mass civilian movements and wars (French revolution, democracies, nazism and communism etc)

How AI's effects on society will turn out, no one knows, not even Sam Altman knows. But better to start using it and understanding it, rather than hoping it'll be something you can close your eyes and it'll go away.

Thanks for expanding on the horse stuff!

I also don't know what AI's effects will be, but ... that's why I'm not convinced it will be a "horse" vs a "printing press" vs an "internet" vs a "word processor/photoshop".

From my usage of GPT4 so far, that particular tool is most like "word processor/power tool," but I certainly wouldn't confidently claim that future developments wouldn't be more transformative. But I'm also not convinced they will be.

If we get a 'general AI' any time soon, I do not see how it could not be transformative.

Already LLMs seem really damned good at intent modeling and summarization. That alone is going to have huge ripples in society as we have systems that attempt to classify based on heuristics everywhere, and many of them break easily. It gets a little more worrisome when it comes human monitoring systems because now an AI system can take your audio/visual/textual data and easily (as compared to the past) figure out what your beliefs are.

When we reach general intelligence, that is human level reasoning, the person that can buy the most processors and connect to the most data has a significant advantage over any individual without said computing power.

Knights were a sign of decline, not progress. They dominated West European battlefields for a few centuries, because professional infantry did not exist. States did not have the financial and administrative capacity to have standing armies. They had to rely on local warlords and their unreliable webs of mutual support.

The Byzantine Empire continued to have professional infantry, because they were still wealthy enough and capable enough to support a standing army. They also had horse archers, which had been a key component of the army in the late Western Roman Empire but had almost disappeared in the West afterwards. And before their decline, their heavy cavalry also consisted of professional soldiers instead of individual warriors.

Professional infantry reappeared in the West in the late middle ages in the form of mercenaries. Then it turned out that pikemen were generally more effective than knights. While a charging horse is big and scary, it's not actually large enough to crash through infantry lines. If the infantry doesn't chicken out, the charging knight has to.

Pikemen alone are not good enough against knights. Pepper pikemen with skirmishers (bows + thrown spears), and they'll eventually break. The pikemen cannot charge the cavalry in open terrain, or they'll lose formation and get annihalated. If pikes worked well, the byzantine empire would have never needed cataphracts, just follow their Macedonian ancestors and revive the greek sarissas. Its pike and shot that pushed knights out. Only then did civilian armies have effective ranged options that could threaten knights.

Also the byzantine empire got eventually destroyed by the turks The byzantine government which relied on tax collector->emperor->soldier was less efficient than the simplicity of the knight->king structure of the turks. The more aristocratic Franks and Spaniards had no problems pushing back the moors, because turns out the motley crew of vagrant crusaders were more effective than an easily corruptable bureaucracy.

Pikemen dominated European battlefields after advances in infantry tactics made them effective. Pike and shot was a later development that replaced pure pike squares long after pikemen had ended the dominance of heavy cavalry.

The key development in the pike square was mobility. Earlier infantry forces using similar weapons had more rigid formations, with a single direction that was supposed to point towards the enemy. That made them vulnerable to outflanking by cavalry / skirmishers / archers. Pike squares drilled rapid turns, which made outflanking them much more difficult.

The Byzantine Empire remained capable and strong until around 1200, when a series of incompetent emperors destroyed it. In particular, one of them had the clever idea of using the Fourth Crusade in a power struggle against another. That resulted in the loss of Constantinople. While the empire eventually got its capital back, it never recovered. The empire that the Ottomans later defeated was only a shadow of its former self.

As for the supposed effectiveness of the Franks and Spaniards: the Reconquista was a series of wars from 718 or 722 until 1492.

The Byzantines where shocked when they first encountered knights in southern Italy in the 1000s. They where crushed by the Normans. Cavalry charging full speed ahead with crouched lances was a huge innovation. The norm since forever was for cavalry to approach orderly at walking pace to stay in formation. Horses really don't want to trample anything. The whole knight charge became kind of lost art later as we can tell from something like Waterloo where the cavalry faced the squares of infantry and the horses just started circling around them refusing to engage as they got shot down.

Military tactics don't necessarily scale. Knights where probably optimal at the 10k-20k army size range, but there wouldn't be able to scale to the size of say Alexandrian battle (47k vs 120k).

I assume you are referring to the Battle of Dyrrhachium. The new thing was not the cavalry charge with lances (which was a standard practice for the Byzantines as well) but charging with couched lances. That, when combined with specific changes in equipment, made the charge more effective.

In the bigger picture, the Byzantine Empire lost the battle but ultimately won the war. That marked the end of decline for the empire and started the Komnenian restoration, making the Byzantine Empire a major military power for the next century.

The cavalry charge became a lost art, because people learned how to counter it. Even during its heyday, heavy cavalry was vulnerable to feigned retreat tactics, possibly for psychological reasons. Byzantines used it to defeat Normans at Larissa a year after Dyrrhachium, and Mongols later used it effectively in their invasions of Poland and Hungary. And around the time of the Hundred Years' War, infantry had learned how to hold its ground against cavalry charges.

As I said, the innovation of the Medieval Knight was "charging full speed ahead with crouched lances". "Charging" cavalry, in that sense, was not a thing before. Byzantine Cataphracts fought like all known cavalry of antiquity: they didn't crash into enemy formations, they slowed down and attacked like infantry trying to maintain formation.

  The cavalry charge became a lost art, because people learned how to counter it

I don't know, mounted knights charging where dominant from the mid 1000s until around Agincourt (1415), that's a long time to find a specific counter. What happened imho, is that armies got big again to the point where the charges wouldn't scale anymore. Armies started resembling more the classical period: the landschneckts, and specially the Spanish Tercios resemble Alexander's armies a lot.

And as for being a lost art, the art was really in the breeding and teaching horses to trample through a formation. I imagine it would have been a useful resource in later periods, it's not as there where no <8k unit battles anymore. It's just that since that wasn't the META for the important battles nobody could justify maintaining such an expensive skill.

Crashing into enemy formations was not a thing, because it was not survivable for the horses. Because horses are not large enough to crash through 10 or 16 ranks of infantry, their momentum works against them. Elephants could do that, but not horses. Crashing through a loose formation was possible, as was making a dense formation panic and flee.

As I mentioned, the immediate counter to a cavalry charge was feigned retreat. It worked, because it looked very much like a successful charge. You charge, the enemy breaks formation and flees. You give chase, but you are a bit too eager and proceed a bit too far. Then you find yourself in a trap, exhausted and surrounded.

You mentioned Agincourt, but the Battle of Crécy (1346) was similar but larger.