Stage Direction: [Mr. and Mrs. Martin are seated like the Smiths at the beginning of the play. The play begins again with the Martins, who say exactly the same lines as the Smiths in the first scene, while the curtain softly falls.] (564)
It looks like in the world of the play the past is the present and the present is the past. It's really no wonder that everybody has so much trouble keeping things straight. If you lived in a reality where past and present were indistinguishable from one another, your memory would probably be pretty sketchy as well.