1. "Everything in the past is a preface." From the beginning of Shakespeare's play The Tempest, it is one of Shakespeare's famous sayings.
2. The ancients also said, "Everything in the past is a preface!" A similar famous saying, "The cold corner is gone, mulberry is not late" is a famous saying in the preface to Tengwang Pavilion, a famous work by the poet Wang Bo in the Tang Dynasty.