Possible future

Speaking during the English Civil War, the Second Doctor admitted to Polly Wright that he had seen or heard of "all kinds of" possible futures from the "great" to "truly terrible", which were "all out there". He acknowledged Englands with a third, fourth, or fifth Civil War, a resurgent monarch who ruthlessly oppressed all democracy, a triumphalist, hereditary Puritan Protectorate that ruled the country until the 20th century, or an invading Catholic army which took advantage of England's crisis to take over most of the known world. (PROSE: The Roundheads)

The Thirteenth Doctor told her companions that Orphan 55 was only a "possible future" for the Earth of 2020. (TV: Orphan 55)