庄子 - 齐物论

昔者庄周梦为蝴蝶，栩栩然蝴蝶也，自喻适志与，不知周也。

俄然觉，则蘧蘧然周也。

不知周之梦为蝴蝶与?

蝴蝶之梦为周与？

I don't really understand what this excerpt is trying to imply, but I think it somehow sounds nice.