What the Japanese Toilet Taught Me About Human Nature
I used to work at Google, and from time to time I visited the Googleplex, the company headquarters in Mountain View California. It’s famous around the world for its quirkiness and how it spoils Googlers. I could talk about the lap pool, the slide, but today I'll focus on its most philosophically interesting asset: the Japanese Toilet.
Ample wisdom is embedded into tiny quirks of our world, if we only care enough to find it. Today I'll tell you how learned people don't judge things objectively and instead just copy others, all from reflecting on1 the Japanese Toilet.
The Japanese Toilet
For those unlucky enough to never have experienced the glory of this eastern invention, here's a primer. Different models have more or less features, but the main one is an electronically activated warm water jet that cleans your nether regions at a click of a button.

To understand why the Japanese Toilet is the superior technology, imagine you had had a warm chocolate stain on your arm and were trying to wipe it clean with a paper towel. Obviously, you would wash it instead. The fact that you can do that remotely on the Japanese Toiler makes it the most hygienic option too.
So, this is the enigma I want to answer in this essay: why do people in developed countries don't adopt the Japanese Toilet, even though it's the clearly superior technology?
It's Hard to Judge Things Objectively
Suppose you wanted to buy a mid-sized SUV and were torn between a Toyota and a Honda. Deciding which one is better requires vast amounts of domain knowledge you don't have, such as how different drivetrains perform at different torques, and how to interpret safety test results. Not only that, but there is no single notion of the "best" car. Is fuel economy more important than a comfortable ride? Each person values aspects of a car differently. Given the difficulty of the evaluation, people just don't do it. Instead, they just do what everyone else is doing.2
You might think choosing a car is a rare, complicated task, and that we are more objetive on simpler everyday decisions. Well, no. We are remarkably irreflective on even the simplest of tasks: how we wipe ourselves.
People Aren't Dumb, the World is Hard
Suppose you were walking in a forest and found an unknown berry tree. Imagine the amount of knowledge you would need to know whether it's safe to eat its berries. It's likely the average biology PHd couldn't do it. Nevertheless, people were eating berries before there was even such a thing as biology.
The world is just too complicated3, and we are built to survive despite not understanding it. We do that by copying others. We eat the berries only if everyone is eating them. We buy the Toyota because our neighbor did it. And we use toilet paper rather than the superior Japanese Toilet because that's what everyone does.
Think from First Principles
Humans can carefully consider decisions. We just don't do it all the time since it's metabolically expensive and slow. In the Savanah, you don’t have time to philosophize about the needs and wants of the lion, you just run!4.
There is a lot of wisdom in listening to one’s gut, but we can also be careful and deliberate in our reasoning. We can think from first principles, if you will. In the modern world, we have hours or days to consider important decisions, and usually our lives are not at stake, so we should be more reflexive and less instinctive. We should be objectively asking what is best rather than just copying others so much.
Question Handed-down Knowledge
Sometime ago I was asking for advice on what database to use for a project on a large CTO group chat. Some guy DM'ed me to use Mongo. According to him it was performant and had worked well for him in the past. One way I could have taken this advice is that since it was a good option for him, it would be for me too. If he was eating the berries, they would not poison me.
But I could do better. What does “performant” even mean?5 Instead, I needed to build a mental model of the best way to use Mongo, with features such as:
What are the pros and cons of schema-less DBs6?
How does mongo scale vs a traditional SQL DB for the expected size of my workload?
How expensive is Mongo vs a SQL SB and how tied I will be to one provider?
I asked some of these questions to the guy who gently offered the advice, and it was clear his analysis was shallow. He was clueless, and by copying him I would be clueless too. Maybe I would have succeeded anyway, but it would have been dumb luck.
In Conclusion
Something as simple as how do you use the toilet is full of philosophy about human nature. By reflecting on such mundane things, you can rise above the unreflective masses and take better decisions. Maybe, you will even adopt the Japanese Toilet.
And I mean I was thinking about it, not (only) sitting on it.
This makes perfect sense from an evolutionary perspective. People had to choose what to eat before there was no knowledge of biology. You most likely won't get poisoned if you eat what everyone else is eating.
The title of this section comes from a Freakonomics podcast episode with Nobel winner economist Richard Thaller.
The book "Thinking, Fast and Slow" by Nobel winner economist Daniel Kahneman popularized the duality between instinctive, fast, cheap, and imprecise thinking (System 1) versus the conscious, slow, effortful, logical form (System 2).
Performant in what metrics, for what task, under which constraints, compared to what option?
Schema-less data is always a mistake. The valid alternative is between enforcing the schema at the application or at the DB level. Mongo does the former while SQL does the latter, though the boundary is blurred, since you can encode schema rules in mongo or store schema-less JSON in SQL DBs.