Is それが人生{じんせい} , 仕様{しよう}が無{な}い, or something else the most natural equivalent to "that's life", "c'est la vie", etc?

Question

For years I have been saying それが人生{じんせい} in Japanese to mean "such is life" / "c'est la vie". In fact English has a few other ways to express the same thing, and so do the other European languages I am familiar with.

Well my Japanese friends and acquaintances always understood, seemed to enjoy it, and never corrected me.

On my current trip to Japan I also learned 仕様{しよう}が無{な}い as having a similar meaning, perhaps literally more like "it can't be helped".

But only this morning for the first time have I been told that the first one is not actually a set phrase in Japanese, that it's merely the literal translation of the English (or French) phrase into Japanese.

So is it true that only 仕様が無い is used in idiomatic Japanese or is it just that the person who corrected me just isn't used to それが人生 even though other people in other parts of Japan, or people of other generations, might use it in their normal speech?

And what about other ways to express this sentiment? Since I originally asked this question people have added other variants in comments:

• 世の中はそんなもんだ
• 人生ってそんなもんだよ

Is one any more idiomatic, natural, Japanese-sounding? Is this a sentiment Japanese actually express at all?

Answer 1

「それが人生」, while everyone will understand it, does sound pretty "translated". You will probably hear it more often in fiction than in real life.

Thing is 「人生」 is a bigger word for us than "life" is for you. When we talk about an "everyday" kind of life, we use 「[生活]{せいかつ}」 or 「[暮]{く}らし」, not 「人生」. 「人生」 sounds more long-term and philosophical, which is why 「それが人生」 sounds a little too dramatic and/or profound for everyday use.

For everyday use, 「しようがない」 or 「しかたがない」 would sound much more natural.