Spinoza ends his Ethics book - one of the most demanding works in the history of philosophy - with a single sentence: “Sed omnia praeclara tam difficilia quam rara sunt.” All things excellent are as difficult as they are rare.

I keep coming back to this line as I watch the AI conversation unfold. Not because it’s a clean argument against AI. It isn’t. But because it names something we’re losing sight of in the rush toward effortless generation: excellence has conditions, and we’re quietly removing them.

The AI Middle Ages

There’s a growing argument that we’re not in an AI revolution comparable to the Industrial Revolution. We’re in something more like the Middle Ages - a transitional period where a powerful new capability exists, but we haven’t figured out our relationship with it yet.

Will Rinehart makes this case in a recent essay. In the medieval period, creative production was “a negotiation between patron and maker, oriented toward something transcendent. The Sistine Chapel happened because Julius II and Michelangelo fought. Work emerged from friction, not selection.” AI, he argues, is flipping this relationship again - but toward effortless selection from infinite options.

We have enormous productive capacity. What we lack is the cultural and philosophical framework to use it well. That’s what makes it a Middle Ages, not an Industrial Revolution. The technology isn’t the bottleneck. The meaning is.

The inspiration chain

The Renaissance worked because humans looked backward before they leaped forward. Scholars rediscovered Aristotle, architects studied Roman ruins, artists revisited Greek proportions. The achievements they found were clearly human - products of struggle, craft, and intention. And those achievements inspired people to go further.

This is the “human inspires human” chain. It’s not just about influence in the artistic sense. It’s about recognizing difficulty in someone else’s work and feeling compelled to match it. You read a passage that clearly cost the author something, and it pushes you to try harder. You see a proof that took decades of failed attempts, and it shapes your sense of what’s worth pursuing.

Zack Kass, formerly of OpenAI, wrote a book called The Next Renaissance, framing AI as the catalyst for a new golden age of human potential. But even he identifies the core risk: what we face is “an identity displacement crisis, not a job displacement crisis.” The question isn’t whether AI takes our jobs. It’s whether it takes the things that make us feel like our work matters.

Habsburg AI

There’s a technical version of this argument that makes it harder to dismiss as nostalgia.

When AI models train on AI-generated content - which is increasingly unavoidable as AI output floods the internet - they degrade. Outputs drift toward the average. Rare perspectives, minority voices, unusual styles - the edges of what’s possible - get trimmed away. Researchers call this “model collapse.” The popular metaphor, coined by Jathan Sadowski, is “Habsburg AI” - a reference to the royal dynasty whose inbreeding led to its own extinction.

The connection to Spinoza is hard to miss. Model collapse eliminates exactly what Spinoza says defines excellence: the difficult and the rare. What survives repeated AI-on-AI training is the easy and the common. The median. The safe answer. The thing that, by Spinoza’s definition, cannot be excellent.

And it’s not just a technical problem. If the next generation of humans grows up surrounded by AI-generated content - and some studies suggest AI-generated text already accounts for roughly half of new articles on the web - the inspiration chain breaks. Not because AI content is necessarily bad, but because it lacks the human struggle that makes prior work inspiring. You don’t look at an AI-generated essay and think: someone poured years into understanding this deeply enough to write it. The friction is absent. And without friction, there’s nothing to push against.

And the economics make it worse. If AI can produce good-enough content at near-zero cost, fewer people will be able to make a living creating things. Fewer professional creators means less human-made work for the next generation to be inspired by - and less human data for future AI models to learn from.

Difficulty as a feature, not a bug

The optimists point to historical parallels. Photography didn’t kill painting - it liberated Impressionism. Calculators didn’t kill mathematical thinking. Each time, creative humans found new territory that the technology couldn’t reach.

This is probably right, as far as it goes. But it misses Spinoza’s deeper point. He’s not saying difficult things are better. He’s saying excellence and difficulty are the same thing. The difficulty isn’t an obstacle to be overcome on the way to the excellent result. The difficulty is what makes the result excellent. Remove it, and you haven’t streamlined the path to excellence - you’ve eliminated the conditions under which excellence can exist.

What’s actually at stake

I don’t think this is an argument against using AI. I use it extensively in my daily work. The question is more specific: can we preserve the conditions for excellence in a world where everything is easy to produce?

The Renaissance didn’t happen because people had easy access to Greek texts. It happened because rediscovering those texts was hard enough to filter for people who cared deeply. The difficulty was the selection mechanism for seriousness. When everything is available instantly and effortlessly, that selection mechanism disappears.

Spinoza was a lens grinder by trade - a craftsman who understood that precision comes from patient, skilled labor. He wrote the Ethics over years of careful thought, and it was only published after his death because the ideas were too dangerous for his lifetime. The book itself is a living proof of its final line: excellent, difficult, rare.

The challenge for our AI Middle Ages is to figure out what comes next. Not to reject the technology, but to build the cultural and philosophical frameworks that ensure difficulty and rarity still have a place. Because if Spinoza is right, and I think he is, removing difficulty doesn’t make excellence easier to reach. It makes it harder to find.