没有什么快乐不快乐
[méi yŏu shén me kuài lè bù kuài lè]
It roughly translates to 'there is no such thing as happy or unhappy', which expresses a sense of emotional indifference or tranquility that comes from not being overly influenced by happiness or sorrow. The holder probably desires or advocates a mindset of remaining calm and unperturbed in all situations.