mirth（n.）
古英语 myrgð “快乐，愉悦，永恒的幸福，救赎”（原始意义现已过时），源自原始日耳曼语 *murgitha（源头还包括中古荷兰语 merchte），是 *murgjo- 的质量名词（参见 merry； 还参见 -th（2））。到13世纪初，“表达或展现幸福，欢乐”的意思已经出现； 到14世纪中期，“愉快，欢乐，欢腾的状态或感觉”已经出现。 Mirthquake “引起抽搐笑声的娱乐”首次出现于1928年，指的是哈罗德·劳埃德的电影。
I HAVE always preferred chearfulness to mirth. The latter, I consider as an act, the former as an habit of the mind. Mirth is short and transient, chearfulness fixed and permanent. Those are often raised into the greatest transports of mirth, who are subject to the greatest depressions of melancholy: on the contrary, chearfulness, though it does not give the mind such an exquisite gladness, prevents us from falling into any depths of sorrow. Mirth is like a flash of lightning, that breaks through a gloom of clouds, and glitters for a moment; chearfulness keeps up a kind of day-light in the mind, and fills it with a steady and perpetual serenity. [Addison, "Spectator," May 17, 1712]
我一直更喜欢愉快而不是欢乐。我认为后者是一种行为，前者是一种思维习惯。欢乐是短暂的，而愉快是固定和永久的。那些经常陷入忧郁低谷的人往往会被带到最大的欢乐之中； 相反，愉快虽然不能给人带来极度的快乐，但可以防止我们陷入任何深度的悲伤。欢乐就像闪电一样，穿过阴云，闪耀一瞬间； 而愉快则在心中保持一种白昼，并使其充满稳定和永久的宁静。[Addison，“观察家”，1712年5月17日]