As long ago as the 14th century(时间状语),an Englishman(主语),Sir John Hawkwood(主语的同位语),made(谓语) the remarkable discovery(宾语) that people would rather pay large sums of money than have their life work destroyed by gangsters(同位语从句,修饰并等同于discovery).
have their life work destroyed:令其生活工作被别人毁坏
这是have sth.done的用法,意思是让别人做某事.有have做谓语就不能再加系动词了,过去分词done本身就可以表被动.