translation - Interpretation of a sentence by Mishima

In Yukio Mishima's "The Temple of the Golden Pavilion," (三島由紀夫によって書かれた「金閣寺」) one of the characters, Kashiwagi, writes a sentence over a poster:

未知の人生とは我慢がならぬ。

Here is the passage:

それは日本アルプスを描いた旅行協会の美しい石版刷で、青空に浮かんだ白い山頂に、 「未知の世界へ、あなたを招く！」という活字が横書きになっていた。柏木は毒々しい朱筆で、その字と山頂を斜め十文字に抹消し、さてかたわらには、内反足の歩行を思わせる彼の踊るような自筆が、「未知の人生とは我慢がならぬ」と書きなぐっていた。

In the English translation the sentence is written as,

I can't stand an unknown life.

Do you think this is the best translation? Would the following be more accurate in meaning?

I won't put up with an unknown life.

I guess my suggestion may be more faithful in meaning, but on second thought, perhaps the tone of the sentence is more faithfully translated in the book's attempt. Looking at the ならぬ, I think I remember the ~ぬ negation being literary in tone, which is not really reflected in the translation (but that might be asking too much.) Is this correct? What do you think about the translation?

I have some other specific questions:

In English the phrase, "an unknown life," is odd because it is ambiguous in meaning and can be interpreted in so many ways. It can mean "the life of an unknown person" ie, living an anonymous life. Or it can mean "a life about which nothing is known-- a life that we cannot understand."

Is the meaning open to this much interpretation in the japanese phrase, "未知の人生"?

Does the phrase, "未知の人生" sounds odd in japanese?

Answer

FWIW, I would prefer the original translation. When you say "I won't put up", there's a hint of your going to do something about it. When you say "I can't stand", there's no such intent of actions, and that is consistent with the original Japanese version.

"未知の人生" is indeed ambigious as you say, even in Japanese. But in this case, there's "未知の世界" that appears immediately before this, which means "the world you haven't seen" in this context. So one would assume both "未知の" have the same meaning.