What you don't see won't hurt you = Remaining ignorant or uninformed about something will allow you to not have the sense of responsibility to worry or think about it.
A: "Where are you going?"
B: "It's better that you stay in the dark about this. What you don't know won't hurt you."
The best thing is to turn a blind eye = Turning a blind eye is an idiom describing the ignoring of undesirable information. The phrase to turn a blind eye is attributed to an incident in the life of Admiral Horatio Nelson. Nelson was blinded in one eye early in his Royal Navy career.
What you don't see won't hurt you = 何かについて知らなかったりしたらそのことについて心配したり考える必要がない。
（英文）
A: "Where are you going?"
B: "It's better that you stay in the dark about this. What you don't know won't hurt you."
（訳）
A:「どこ行くの？」
B:「知らない方がいいよ。知らないことによって傷つくことはないからね。」
The best thing is to turn a blind eye
=a blind eye はイディオムで、必要性のない情報を無視することです。このフレーズはAdmiral Horatio Nelsonから由来しています。Nelson は Royal Navyのときに片目が失明してしまいました。
We can say "The best thing to do is to ignore it."
"The best thing to do is to ignore it.- If something is bothering you the best thing is for you to ignore it. This means you do want to concentrate on the issue because it affecting you so its best to pretend like its not happening.
"The best thing to do is to ignore it."といえます。
"The best thing to do is to ignore it.-何かが嫌な場合一番の対処法は無視をすることです。これはある出来事に対してあまり考えすぎたくないため見て見ぬふりをするという意味です。
There are many phrases that can be used. These all convey the idea that it is best not to know. You will not pay attention to whatever the situation may be.
"Ignorance is bliss" is a phrase in the English language which is used often when someone learns of bad news. What is implied is that they wish they did not know the information even if it is necessary.
"Ignorance is bliss"（知らぬは仏）とは、誰かが悪いニュースを知ったときによく使われる英語のフレーズです。それが必要だったとしても、知らないほうがよかったということを意味します。
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