Please Translate

Please write the following quote in Japanese writing:

"Our sweetest songs are those that tell of saddest thought."

hi!
I found a Japanese blog that explains this poetry.

http://blogs.yahoo.co.jp/tsu4132/archive/2012/2/4

In this blog, there's a translation by Japanese famous writer, Soseki Natsume.

quote)
　We look before and after
　　　　And pine for what is not:
　　Our sincerest laughter
　　　　With some pain is fraught;
　　Our sweetest songs are those
　　　　that tell of saddest thought.

前をみては、後(しり)えを見ては、物欲(ものほ)しと、
あこがるるかな　われ。
腹からの、笑といえど、苦しみの、そこにあるべし。
うつくしき、極(きわ)みの歌に、悲しさの、極みの想(おもい)、
籠(こも)るとぞ知れ」
unquote)

The part you want to translate is,"うつくしき~籠るとぞ知れ"

See you!