A large fraction of that workforce was enslaved, and it's not accidental that the terminology has descended into engine jargon, like master & slave cylinders, clocks, drives, etc. We have replaced the fleshy engines of the ancients with inorganic ones to the general benefit. I hope that's a good portent for the replacement of us fleshy knowledge engines by AI.

The first part if true: Romans did depend on slavery, as did most ancient societies.

I am less convinced that engine jargon is derived from that. Where the terminology is master and slave specifically, yes, but not necessarily in slave societies. Where the terminology is master and something other than slave, I do not think so.

Slave is pretty unambiguous. Master less so. To a middle aged British bloke like myself the strongest association of master that I grew up with was "male school teacher". Master craftsman is also a significant association.

He specifically said "master & slave." IDE master-slave drives are also "derived from slavery" simply because that's what "slave" means, even though the analogy doesn't make much sense (the master drive doesn't control the slave drive and isn't superior to it).

Exactly master come from the latin magister which mean the school teacher, the slave owner in latin is dominus (dominion , dominate etc.)

Difference being that knowledge work can actually be fun.

To me the difference seems to come in with “mass industrialization” or de-personalization.

I’m growing my own backyard vegetables? Challenging but rewarding. I’m part of massive factory farming? Less enthused.

I think this can be generalized across a lot of industries, and I think it boils down to our human need to feel like we’re more than just a small cog.

Why isn't optimizing for factory farming not fun? You might mean the loss of autonomy.

Loss of autonomy is definitely a factor, but also people can get disconnected from the output leading to a loss of meaning in the actual work. At industrial scales vegetables are an intermediate step in a production / distribution chain where the desired output is actually dollars. If dumping or mulching them results in more dollars, so be it. If it tastes worse but transports better and you get more dollars, worse tasting it is. Etc etc.

You could say that the optimisation process itself results in a loss of autonomy since market structure, competition and regulation dictate what you have to do to a large extent. "Don't hate the player, hate the game...".

I think knowledge work can go the same way.

Theory of alienation in Marxism usually refers to the idea that social hierarchies exist because they're tied to your work. Optimization isn't strictly just production based, it can be carbon capture. Then you get to Marx's other theory: the commodity fetishiation. It's not all doom, you can fetishize some crops by making them organic, carbon negative, low water, etc.

All of knowledge work is very alienating.

Physical work can be fun too!

Neither as much when you're a slave of course.

It's fun as a hobby. It may be fun to work with your hands. I haven't heard people who do heavy labor their whole lives talk about it as fun. It's brutal to do it every day for decades, causes a lot of pain and injury, and just imagine getting out of bed for it, again, when you're 50.

This is a slight digression, but I strongly suspect that master/slave in technical contexts originated as a pun. It was normal practice to refer to a canonical or primary object as the "master _____", with the same meaning as "main". My guess is that some point someone wanted to refer to a subordinate object, noted that "master" can also mean "owner of a slave", and the obvious pun fit well enough to stick.