이성
iseong[ˈi(ː)sʰʌ̹ŋ]
In Korean, 'reason' (referring to the capacity for rational thinking) is 이성 (iseong). Wiktionary also lists 이치 (ichi).
Meaning: (the capacity of the human mind for) rational thinking (noun)
Ways to say it
| Korean | Romanization (Wiktionary) | IPA |
|---|---|---|
| 이성 | iseong | [ˈi(ː)sʰʌ̹ŋ] (SK Standard, Seoul, narrow) |
| 이치 | ichi | [ˈi(ː)t͡ɕʰi] (SK Standard, Seoul, narrow) |
The term 이성 refers to the human capacity for rational thinking. If you wish to use 'reason' as an adjective meaning 'rational', you can use the form 이성적 by adding the suffix –적 to the noun. Note that while these terms describe the mental faculty, the standard Korean word for a 'reason' (as in a cause or motive) is 이유.
What does it mean word for word?
The word 이성 is a homonym.
Which one should you use?
While 이성 refers to the human capacity for rational thought, 이치 refers to the underlying logic or principle of how things work in the world.
How do you pronounce it?
iseong
Did you know?
- Because 이성 is a homonym, it can also mean 'the opposite sex' in a social context. While it can describe 'reason', it is frequently used to talk about 'the other gender' in everyday conversation.
- The term 이성 can even be associated with the concept of 'different stars' (異星) through different Hanja combinations. This demonstrates how much the specific Chinese characters change the entire meaning of the sound.
- In historical Korean texts, the concept of 이성 was heavily influenced by Neo-Confucianism, which viewed rational order as the fundamental structure of both the human mind and the state.
Examples in context
- 이성을 따르라.Obey reason.This sentence is useful for practicing the command to obey 이성.Tatoeba #11110767 by intertime, translation #8784004 by jimkillock
- 경험과는 무관한 인간 사상의 산물인 수학이 어떻게 현실의 대상에 그렇게나 훌륭하게 잘 들어맞을 수가 있지? 그렇다면 인간의 이성은 경험 없이, 단지 생각만으로, 실제 사물의 속성을 추측할 수 있는 건가.How can it be that mathematics, being after all a product of human thought which is independent of experience, is so admirably appropriate to the objects of reality? Is human reason, then, without experience, merely by taking thought, able to fathom the properties of real things.This sentence explores the relationship between human 이성 and the properties of reality.Tatoeba #8734963 by Eunhee, translation #2725867 by Hybrid
- 모든 인간은 태어날 때부터 자유로우며 그 존엄과 권리에 있어 동등하다. 인간은 천부적으로 이성과 양심을 부여받았으며 서로 형제애의 정신으로 행동하여야 한다.All human beings are born free and equal in dignity and rights. They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood.This sentence demonstrates the concept of being endowed with 이성 and conscience.Tatoeba #532207 by cueyayotl, translation #338182 by sysko
- 예를 들어, 그녀가 결석한 이유를 알고 싶어요.For example, I want to know the reason she was absent.
- 왜 학교에 늦게 왔어?Why did you come to school late?
Example conversation
Dohyun and Minji are discussing a character in a movie who makes emotional decisions.
- 도현 Do-hyeon그 캐릭터는 이성이 부족한 것 같아요.geu kaerik-teureun iseongi bujokhan geot gat-ayo.I think that character lacks reason.
- 민지 Min-ji맞아요, 너무 감정적으로 행동해요.maj-ayo, neomu gamjeongjeok-euro haengdong-haeyo.True, he acts too emotionally.
- 도현 Do-hyeon민지 씨는 이성적인 편인가요?Minji ssi-neun iseongjeogin pyeon-ingayo?Minji, are you the rational type?
- 민지 Min-ji저는 생각을 많이 하는 편이에요.jeoneun saenggag-eul mani haneun pyeon-ieyo.I tend to think a lot.
Sources
- Wiktionary, “reason” translations and entries 이성, 이치, CC BY-SA 4.0, dump of 2026-09-26.
- Word origins: Wiktionary entries 이성, 이치, CC BY-SA 4.0.
- Example sentences: Tatoeba CC BY 2.0 FR.
