Translation guide
The English adjective 'self-evident' describes something that is clearly true and needs no proof. In Japanese, this concept is expressed through adjectives, set phrases, and grammatical patterns that convey obviousness or the idea of 'not needing to be said.'
Describing a fact or truth that is immediately clear without explanation.
Emphasizing that something is so obvious it doesn't require verbalization.
自明 (じめい) is more formal and specifically means 'self-evident' in a logical or philosophical sense. 明らか (あきらか) is a general word for 'obvious' and can be used in everyday conversation. For most casual situations, 明らか or 言うまでもない are more natural than 自明.
The English phrase 'self-evident' is often used in formal declarations (e.g., 'We hold these truths to be self-evident'). In Japanese, directly translating this as 自明の真理 may sound overly stiff or philosophical. In many contexts, a simpler expression like 明らかな事実 (obvious fact) or 言うまでもないこと (something that goes without saying) is more appropriate.
That is a self-evident truth.
Literally 'it goes without saying.' A very common and natural way to express that something is obvious or self-evident.
彼が正直者なのは言うまでもない。
It goes without saying that he is an honest person.
Means 'obvious' or 'clear.' Can be used in many contexts, but is slightly less formal than 自明.
彼の成功は明らかだ。
His success is self-evident.
An idiomatic expression meaning 'as clear as day' or 'obvious as seeing fire.' Used for emphasis.
彼が嘘をついているのは火を見るより明らかだ。
It's self-evident that he is lying.
A set phrase meaning 'needless to say' or 'it goes without saying.' Often used at the beginning of a sentence.
言わずもがな、健康は大切だ。
Needless to say, health is important.
A grammatical pattern meaning 'not to mention A' or 'A is self-evident, and also...' Used to connect clauses.
彼は英語は言うまでもなく、フランス語も話せる。
He speaks French, not to mention English (which is self-evident).