The  Seder  night is not simply the retlling of an event that occurred in antiquity, but the person re-experiencing of the event. This concept observed Rabbi Joseph B. Soloveitchik, is implicit in the very word " Haggadah"  - which can be seen from the phrase " haggadat edut,"  a declaration of testimony. One of the basic principles of the law of evidence is that hearsay, testimony known only to the witness through someone else, is not admissable evidence. In this vein, the Haggadah emphasizes that "a person is obligated to see himself as if he personally left Egypt." Accordingly, the mitzvah of retelling the story of the Exodus cannot be a mere recounting of the chronicle of a historical event. It must be first-hand testimony, an acknowledgement of an event that is in the actual realm of experience of the testifying individual. 


haggadah Section: Maggid - Beginning
Source: The Seder Night: An Exalted Evening: The Passover Haggadah by R. Joseph B. Soloveitchik