理 — Reason, Logic, Principle

Meaning

理 covers a cluster of related ideas: reason, logic, principle, and truth. At its core, the kanji points to the natural order underlying things — the inherent rationale behind why events unfold the way they do.

In everyday Japanese, 理 turns up most often in 理由 (reason), 理解 (understanding), 無理 (impossible — literally "without reason"), and 料理 (cooking — literally "managing ingredients").

Etymologically, 理 is a phono-semantic compound (形声文字). The left side — originally 玉 (jewel/jade) — is the semantic radical, while 里 on the right gives the reading ri. Its earliest meaning referred to the veins and grain patterns found in jade. Those orderly, inevitable lines became the basis for 理's broader sense: the inherent pattern running through all things.

Taught in Grade 2 of Japanese elementary school, 理 has 11 strokes. It turns up across science, philosophy, and daily conversation — one of the more practically useful kanji at N4.

Readings

On'yomi (音読み) — Chinese-derived readings

The on'yomi is リ (ri) — used in nearly every compound word containing 理. You'll hear it in casual conversation, academic writing, and formal speech alike.

理由りゆう (riyuu) — reason, cause
理解りかい (rikai) — understanding, comprehension
料理りょうり (ryouri) — cooking, cuisine
無理むり (muri) — impossible, unreasonable, overdoing it
管理かんり (kanri) — management, control, administration
整理せいり (seiri) — arrangement, organization, tidying up

リ appears in all of these. Whenever 理 pairs with another kanji, this on'yomi is virtually always the right choice.

Kun'yomi (訓読み) — Native Japanese readings

The kun'yomi is ことわり (kotowari) — reason, logic, or natural principle. It's literary, more at home in classical texts and proverbs than in daily speech. Still, knowing it makes the kanji's core meaning click into place.

理ことわり (kotowari) — reason, logic, natural order (literary use)
道理どうり (douri) — reason, right, justice, moral law

In practice, ことわり rarely stands alone in modern Japanese. When you want to say "reason," reach for 理由 (りゆう) instead.

Common Words & Compounds

理 shows up across a surprisingly wide range of everyday words. Here they are grouped by theme.

Daily Life & Practical Use

料理りょうり (ryouri) — cooking, dish, cuisine
無理むり (muri) — impossible, unreasonable, too much
修理しゅうり (shuuri) — repair, fix
整理せいり (seiri) — organize, sort out, tidy up

Thinking & Communication

理由りゆう (riyuu) — reason, cause, grounds
理解りかい (rikai) — understanding, comprehension
論理ろんり (ronri) — logic, reasoning
道理どうり (douri) — reason, sense, right

Management & Control

管理かんり (kanri) — management, administration, control
処理しょり (shori) — processing, handling, dealing with
代理だいり (dairi) — proxy, acting on behalf of, agent

Science & Knowledge

物理ぶつり (butsuri) — physics
心理しんり (shinri) — psychology, inner mind
理科りか (rika) — science (school subject)
理想りそう (risou) — ideal, ideals

Example Sentences

彼女かのじょは料理りょうりが上手じょうずです。

Kanojo wa ryouri ga jouzu desu.

She is good at cooking.

それは無理むりだと思おもいます。

Sore wa muri da to omoimasu.

I think that is impossible.

理由りゆうを教おしえてください。

Riyuu wo oshiete kudasai.

Please tell me the reason.

先生せんせいの説明せつめいが理解りかいできました。

Sensei no setsumei ga rikai dekimashita.

I was able to understand the teacher's explanation.

部屋へやを整理せいりしなければなりません。

Heya wo seiri shinakereba narimasen.

I have to organize my room.

自転車じてんしゃを修理しゅうりに出だしました。

Jitensha wo shuuri ni dashimashita.

I took my bicycle in for repairs.

この書類しょるいの処理しょりはもう終おわりましたか。

Kono shorui no shori wa mou owarimashita ka.

Have you finished processing these documents yet?

彼かれの考かんがえ方かたは論理ろんり的です。

Kare no kangaekata wa ronriteki desu.

His way of thinking is logical.

子供こどもの心理しんりを理解りかいすることは難むずかしい。

Kodomo no shinri wo rikai suru koto wa muzukashii.

Understanding the psychology of children is difficult.

Related Kanji

昼 — Daytime, Noon, Midday (Kanji N4)
家 — House, Home, Family (Kanji N4)
顔 — Face, Look, Reputation (Kanji N4)
夜 — Night, Evening (Kanji N4)
病 — Sickness, Illness, Disease (Kanji N4)
便 — Convenience, Facility, Communication (Kanji N4)

Memory Tip

Picture the veins running through a piece of jade. The left component of 理 — 王/玉 — represents jade, the stone most prized in ancient East Asia. The right side, 里, gives the reading ri. Early craftsmen observed that jade carries natural grain lines: orderly, inevitable, intrinsic to the stone itself. That image became the foundation of 理 — the natural pattern or principle woven into all things.

Recall those veins whenever you see this kanji: elegant, logical, perfectly ordered. And 無理 (muri, impossible)? Literally "without those natural veins" — something that defies the inherent order of things.