Meaning & Usage
✨ Basic Meaning
も当然だ (mo touzen da) literally means “it is also natural” or “it is only natural.” It expresses that a certain outcome, feeling, or state is entirely expected or logical given the preceding circumstances.
🎯 Primary Function
To emphasize that something is a natural, unsurprising, or obvious consequence of a particular situation or condition.
📋 Grammar Structure
Verb (plain form) + のも当然だ / ことも当然だ
い-adjective (plain form) + のも当然だ / ことも当然だ
な-adjective + な + のも当然だ / ことも当然だ
Noun + な + のも当然だ / ことも当然だ
🎭 Usage Contexts
Formal Situations
Can be used in formal contexts to logically explain or justify a situation, but often in a slightly assertive or conclusive tone. Less common than in informal settings due to its directness.
Informal Situations
Very commonly used in informal conversations to express agreement, understanding, or a “no wonder” sentiment.
Written Language
Frequently appears in articles, essays, and reports when making logical conclusions or observations. Common in news and analytical texts.
Spoken Language
Extremely common in daily conversations to express obviousness or agreement.
💡 Common Applications
Expressing logical conclusions
Used to state that a conclusion is evident based on prior information.
Example: 彼があんなに努力したのだから、合格したのも当然だ。 (Kare ga anna ni doryoku shita no dakara, goukaku shita no mo touzen da.) – Since he worked that hard, it’s only natural that he passed.
Justifying feelings/reactions
Used to validate someone’s feelings or reactions as understandable.
Example: 何度も失敗したのだから、彼が落胆するのも当然だ。 (Nandomo shippai shita no dakara, rakutan suru no mo touzen da.) – Since he failed so many times, it’s only natural that he’s disappointed.
Stating an obvious truth
Used to highlight something that is clearly true or expected.
Example: これだけ暑いのだから、アイスが溶けるのも当然だ。 (Kore dake atsui no dakara, aisu ga tokeru no mo touzen da.) – Since it’s this hot, it’s only natural that the ice cream melts.
Frequency
High frequency in both spoken and written Japanese, especially when expressing logical inferences or agreement.
Difficulty
Intermediate to advanced (JLPT N2). The concept itself is straightforward, but subtle nuances and appropriate contexts require a solid understanding.
Example Sentences
彼が怒るのも当然だ。あんなひどいことを言われたのだから。
It’s only natural that he’s angry. He was told such terrible things after all.
毎日練習したんだから、彼女が上達したのも当然だ。
Since she practiced every day, it’s only natural that she improved.
あのレストランはいつも満席だ。美味しいんだから人気があるのも当然だね。
That restaurant is always full. Since it’s delicious, it’s only natural that it’s popular, isn’t it?
Notes & Nuances
📌 Important Points
Particles の and こと
The particles の and こと nominalize the preceding clause, turning it into a noun phrase that “当然だ” modifies. Both are generally interchangeable in this context, but の is more common in casual speech.
Example: 彼が成功するのも当然だ。(Kare ga seikou suru no mo touzen da.) vs. 彼が成功することも当然だ。(Kare ga seikou suru koto mo touzen da.) – Both mean “It’s natural that he succeeds.”
Emphasis with も
The particle も adds emphasis, reinforcing the idea that “even this” or “also this” is natural. It implies that given the circumstances, the outcome is not just natural, but perhaps even more so than one might initially think, or that it fits perfectly with other expected outcomes.
Example: あんなに頑張ったのだから、彼が成功するのも当然だ。 (Anna ni ganbatta no dakara, kare ga seikou suru no mo touzen da.) – Since he worked so hard, it’s only natural (and expected) that he succeeds.
⚠️ Common Mistakes
❌ Omitting の/こと
✅ Always include の or こと before も当然だ to nominalize the preceding clause.
Incorrect: 彼が怒るも当然だ。Correct: 彼が怒るのも当然だ。The verb/adjective needs to modify a noun, and の/こと acts as that noun.
❌ Incorrect plain form conjugation
✅ Ensure the verb or adjective before の/ことも当然だ is in its plain (dictionary/ta-form) form.
Incorrect: 彼が怒りますのも当然だ。Correct: 彼が怒るのも当然だ。Polite forms are not used here.
🏛️ Cultural Context
Politeness Level: Generally neutral to slightly direct. Can be softened with です/ます forms at the end (当然です/当然だと思います).
Social Situations: Used in a wide range of social situations. Can be used to express empathy or understanding (“No wonder you feel that way!”), or to state an obvious truth without much emotional overlay.
Regional Variations: The core usage is standard Japanese. Regional variations would be in the final auxiliary verbs or particles, e.g., 当然や (関西弁 – Kansai dialect).
🔍 Subtle Differences
も当然だ vs. べきだ
も当然だ expresses what is naturally expected or an obvious consequence. べきだ expresses what “should” be done or what one “ought” to do, implying a moral or logical obligation/recommendation.
When to use: Use も当然だ for natural outcomes. Use べきだ for advice, recommendations, or obligations.
も当然だ vs. はずだ
も当然だ conveys something is a natural outcome or evident. はずだ expresses a strong expectation or probability based on reasoning or information, “it should be/must be.”
When to use: Use も当然だ when something is an undeniable, natural consequence. Use はずだ when you are confident about an expectation, but it might not be a direct “natural” outcome.
も当然だ vs. 当然
当然 (touzen) by itself functions as a noun (naturally, rightfully) or a な-adjective (natural, rightful). も当然だ is a fixed phrase that specifically asserts that something IS natural given prior context, often implying “no wonder.” も adds the nuance of “even this/also this is natural.”
When to use: Use 当然 as a general adverb or adjective. Use も当然だ as a set phrase to comment on the naturalness/inevitability of a specific event or situation.
📝 Conjugation Notes
Verbs/い-adjectives: Plain form + のも当然だ な-adjectives/Nouns: な + のも当然だ Past tense and negative forms apply to the clause preceding の/こと. Example: しなかったのも当然だ (shinakatta no mo touzen da – it’s natural they didn’t do it).
🔊 Pronunciation Tips
The “も” (mo) is pronounced clearly, giving it its emphasizing role. “当然” (touzen) has a flat accent (とうぜん).
🧠 Memory Tips
Think of it as “No wonder! (It’s only natural!)” when something clearly follows from a preceding cause. The も acts like an “even” or “also” making the obvious even more obvious.
Vocabulary List
努力
doryoku
effort
合格
goukak
passing (an exam)
落胆
rakutan
disappointment, despondency
満席
manseki
full (seats), no vacancies
上達
joutatsu
improvement, progress
必死に
hisshi ni
desperately, frantically
驚く
to be surprised
Kanji List
当然
とうぜん
natural, obvious, rightful
努
ど
to endeavor, toil
力
りょく
power, strength
合
ごう
to fit, suit
格
かく
rank, status
落
らく
to fall
満
まん
full
席
せき
seat
上
じょう
up, above
達
たつ
reach, attain
必
ひつ
certain, inevitable
Practice Exercises
彼は毎日ゲームばかりしていたのだから、試験に（ ）のも当然だ。
落ちる
落ちない
落ちた
落ちなかった
あの女優はとても綺麗だから、人気がある（ ）当然だ。
のも
ことも
の
こと
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