In this short post, we will take a look at volitional and non-volitional verbs — a distinction that comes up a lot in grammar explanations but is rarely explained on its own. Understanding it will make structures like ように vs ために, たい, or てしまう much easier to grasp.
The basic idea
Volitional verbs describe actions that are done on purpose — consciously, deliberately, by choice. The subject decides to do something and does it.
Non-volitional verbs describe things that happen to you or come about on their own — states, results, involuntary reactions. The subject doesn't choose for them to occur.
In English, this distinction exists too, but it's rarely named. Compare:
I looked at the painting. — deliberate, you chose to look
I saw the painting. — it just happened, it entered your field of vision
Same logic applies in Japanese.
Common volitional verbs
These are actions you choose to do:
食べる（たべる）= to eat
飲む（のむ）= to drink
勉強する（べんきょうする）= to study
書く（かく）= to write
走る（はしる）= to run
話す（はなす）= to speak
見る（みる）= to look at; to watch
Common non-volitional verbs
These are things that happen, states that come about, or involuntary reactions:
できる = to be able to; to become possible
わかる = to understand
なる = to become
見える（みえる）= to be visible; to be able to see
聞こえる（きこえる）= to be audible; to be able to hear
要る（いる）= to need
ある = to exist; to have
Notice the pairs: 見る vs 見える, 聞く vs 聞こえる. This is a classic example of the distinction:
窓から山が見える。
→ I can see the mountains from the window. (they are visible, it just happens)
窓から山を見る。
→ I look at the mountains from the window. (deliberate action, I choose to look)
Why does this matter for grammar?
Several grammar structures in Japanese are restricted to one type or the other. The most common examples:
ために vs ように
ために requires a volitional verb in the purpose clause — you're actively working toward a goal.
ように is used with non-volitional verbs or negatives — you're hoping for a state to come about.
日本語が話せるようになるために毎日練習する。
→ I practice every day in order to become able to speak Japanese.
たい (want to do) only attaches to volitional verbs. You can't "want to understand" in Japanese using たい the same way — understanding isn't something you do on purpose.
日本語を話したい。 ✅
→ I want to speak Japanese.
日本語がわかりたい。 ⚠️
→ grammatically unusual; わかる is non-volitional
てしまう
With volitional verbs, てしまう often expresses regret about something you did on purpose but wish you hadn't. With non-volitional verbs, it expresses that something happened beyond your control.
食べてしまった。
→ I went and ate it. (I did it, and now I regret it)
財布をなくしてしまった。
→ I lost my wallet. (it happened, it was beyond my control)
A note on context
Some verbs can be both volitional and non-volitional depending on context. 笑う (to laugh) is a good example — you can laugh on purpose, or you can burst out laughing involuntarily. Japanese speakers are generally aware of this distinction even if they never explicitly name it, and grammar structures will reflect whichever meaning is intended.
The more exposure you get, the more naturally you'll start to feel which verbs "take decisions" and which ones just "happen." It's one of those things that clicks over time.
