His key conclusion was that such precognitive visions foresee future personal experiences by the dreamer and not mere general events.

[1] Following a discussion of brain function in which Dunne expounds mind-brain parallelism and highlights the problem of subjective experience, he gives anecdotal accounts of precognitive dreams which, for the most part, he himself had experienced.

[2] Later dreams appeared to foretell several major disasters; a volcanic eruption in Martinique, a factory fire in Paris, and the derailing of the Flying Scotsman express train from the embankment approaching the Forth Railway Bridge in Scotland.

He kept a notepad by his bedside and wrote down details of any dreams immediately on waking, then later went back and compared them to subsequent events in his life.

Based on the results, he claimed that they demonstrated that such precognitive fragments were common in dreams, even that they were mixed up in equal occurrence with past memories, and therefore they were difficult to identify until after the event they foresaw.

He believed that the dreaming mind was not drawn wholly to the present, as it was during wakefulness, but was able to perceive events in its past and future with equal facility.

Within the fixed spacetime landscape described by the recently published theory of general relativity, an observer travels along a timeline running in the direction of physical time, t1.

Neither relativity nor quantum mechanics offered any explanation of the observer's place in spacetime, but both required it in order to develop the physical theory around it.

[4] The theory resolves the issue by proposing a higher dimension of Time, t2, in which our consciousness experiences its travelling along the timeline in t1.

However, Dunne found that his logic led to a similar difficulty with t2 in that the passage between successive events in t2 was not included in the model.

[7] However opinions differed over the existence of dream precognition, while his infinite regress was almost universally judged to be logically flawed and incorrect.

[18] Besides issuing new editions of An Experiment with Time, Dunne published sequels exploring different aspects of Serialism.

He had deliberately chosen to leave this material out of An Experiment with Time as he judged that it would have affected the scientific reception of his theory.

[19] The popularity of An Experiment with Time was reflected in the many authors who subsequently referenced him and his ideas in literary works of fiction.

[20] Dunne's theory strongly influenced the unfinished novels The Notion Club Papers by J. R. R. Tolkien and The Dark Tower by C. S. Lewis.

[22] Other important contemporary writers who used his ideas, whether as a narrative or literary device, included John Buchan (The Gap in the Curtain), James Hilton (Random Harvest), his old friend H. G. Wells (The Queer Story of Brownlow’s Newspaper and The Shape of Things to Come), Graham Greene (The Bear Fell Free) and Rumer Godden (A Fugue in Time).

In Philip Jose Farmer's 1952 science fiction novella The Lovers (expanded into a novel in 1961 & '79) the religion of the Haijac Union derives from Isaac Sigman, a messianic figure of a thousand years prior to the events of the story.

Philippa Pearce's 1958 childhood fantasy Tom's Midnight Garden makes use of Dunne's theory of time and won the British literary Carnegie Medal.

[25] The writer Vladimir Nabokov undertook his own dream experiment in 1964, following Dunne's instructions, and it strongly influenced his subsequent novels, especially Ada or Ardor: A Family Chronicle.