Why Is a Tree “arimasu”, Not “imasu”?

Many Japanese textbooks teach a very simple rule:

🔹living things → imasu,

🔹non-living things → arimasu.

Clear and easy, right?

But let’s test it.

What about a tree 🌲?

A tree is alive. So… Ki ga imasu (There is a tree)?

That sounds strange.

In Japanese, we say: Ki ga arimasu.

Wait… why?

So the rule “living vs non-living” is not enough.

Let’s try another idea.

What about movement?

🔹People and animals move → imasu.

🔹Objects and plants don’t → arimasu.

That seems to work.

So trees don’t move, and that’s why we say arimasu.

Problem solved?

Not quite.

Let’s make it more interesting.

What about a zombie 🧟🧟‍♀️?

Zombies are technically dead… but they move.

So what do we say?

👉 Zonbi ga imasu.

That sounds natural, doesn’t it?

Alright, one more.

Imagine a life-sized Pikachu figure in a shopping mall.

It doesn’t move. It’s not alive.

So… Pikachū ga arimasu (There is a Pikachu)?

That’s fine.

But interestingly, many people would also say:

👉 Pikachū ga imasu. Now the logic is breaking again.

Here’s the key idea.

In linguistics, there is a concept called animacy.

Simply put, it means how “alive” something feels to the speaker.

So even if something is not actually alive, if it feels like it could move or has a presence, people may use imasu.

That’s why Pikachu can be imasu.

So what is the real rule?

In fact, there isn’t just one clear rule.

In Japanese, people choose between arimasu and imasu based on a combination of factors:

🔹whether something is living or not

🔹whether it can move

🔹how “alive” it feels (animacy)

These elements are considered together, not separately.

And this is not just about Japanese. This is the reality of natural language.

Natural languages are not built like mathematics, with perfectly clear rules from the beginning.

First, people use the language.

Then, rules are created to explain it.

So if something doesn’t fit perfectly, that’s completely fine.

In natural language, things are often a bit flexible, and meaning can change depending on context and perception.

And that is exactly what makes language so interesting✨

Taichi