Background: mctaggert is a philosopher about 100 years old that said that the A series of time, which is flux rather than block time, was such that it mustn't be real, cos there's no way to say that an event has only one tense, if it will at some stage have every tense.
Preliminaies: In the A series things seem to be in flux whereas the D series is the illusion of something, death, getter closer and staying the same length away: because I know that thing is not present and so never will be.
The A series is like a dream inside the D series which is like a dream inside the A series.