||In a much discussed paper, John McTaggart argues that time is unreal. He argues for this surprising conclusion by claiming that two candidate ways of construing time are inadequate. McTaggart notes that we can order times according to whether they are past, present or future and by how far into the past or future they are. He calls this ordering of times the 'A-series'. He also notes that we can order times according to whether they are earlier than or later than one another. He calls this ordering of times the 'B-series'. He goes on to argue that time cannot be construed in terms of the A-series nor in terms of the B-series. From this he concludes that time must be unreal. His reason for thinking that the A-series is inadequate is because he thinks such an ordering leads to contradiction. He claims that the properties of being past, being present and being future are incompatible, yet each time would have to possess all three, which he deemed impossible. McTaggart claims that the B-series is also inadequate because it cannot account for change. If one time is earlier than another, then this fact holds eternally. However this eternal fact cannot accommodate the fact that what times are past, present and future changes from one moment to the next. McTaggart's argument for the unreality of time is, no doubt, highly controversial and has spurred a great deal of discussion in both trying to clarify it, as well as evaluate it.