天若有情 has a cantonese and chinese version of the song. In chinese the version is 追梦人.

It came from 天若有情天亦老, a poem by 李贺 titled 金铜仙人辞汉歌.

茂陵刘郎秋风客，
夜闻马嘶晓无迹。
画栏桂树悬秋香，
三十六宫土花碧。

魏宫牵车指千里，
东关酸风射眸子。
空将汉月出宫门，
忆君清泪如铅水。

衰兰送客咸阳道，
天若有情天亦老。

携盘独出月荒凉，
渭城已远波声小。

From Bai Du

“天若有情天亦老”这一句设想奇伟，司马光称为“奇绝无对”。它有力地烘托了金铜仙人（实即作者自己）艰难的处境和凄苦的情怀，意境辽阔高远，感情执着深沉，是千古名句。

这句话在古代就早已闻名，很多文人雅士就以此为上联，做对子，看谁对得好。宋代就有个叫石曼卿的人，一语既出，惊动四座，众人皆五体投地。这件事记载在《蓼花州闲录》中。

石曼卿对的是：天若有情天亦老，月如无恨月长圆。

In the Chinese version of 追梦人, the author was 罗大佑

罗大佑 is extremely prolific and multi talented. In 三毛 last work 滾滾紅塵 , he authored the song too.

Actually to write a thesis of 80 -150 000 words is easy compared to squeezing the essence of a novel or a thought into the seven characters per line limitations of a poem or the 4 minute plus time frame of a song.