Some science behind the scenes

Hypnagogia

Dali used hypnagogia to get his inspiration

Hypnagogia and hypnagogic are not methods they are states.

The adjective "hypnagogic" is a term coined by Alfred Maury for the transitional state between wakefulness and sleep.  It is a synonymous term for the trance state induced during hypnosis or during befuddlement, relaxation  or during meditation.

Early references to hypnagogia are to be found in the writings of AristotleIamblichus,  Cardano,  Simon Forman and Swedenborg.  Scientific enquiry of the phenomenon continued in the 19th century with Johannes Peter Müller, Jules Baillarger and Alfred Maury, and continued into the twentieth with Leroy.

Francis Galton provided one of the first systematic investigations of hypnagogic hallucinations in his 1883 book Inquiries into Human Faculty.

The types of spiritual experiences that have occurred during this "threshold consciousness" phase include visual and audio hallucinations, invisible input such as inspiration, improved and pure perception and out of body experiences – so the full gamut.

The person can control the duration of the experience, remember the experience and also, in well-practised individuals, induce the experience at will, but it differs from lucid dreaming – which is not dissimilar in effect, by being a technique which is used while you are awake, whilst in lucid dreaming you are asleep.

NOTE:  There are some sources who now make the distinction between spiritual experiences had on going to sleep and those had on waking up, calling them hypnagogic and hypnopompic.  As the original term was intended to be a state and not an indication of a time of day, I have not made this distinction. 
Given that some people have these dozing on the couch with no intention to go to sleep; and some people have had them in the middle of the night and have no idea whether they were waking or about to go to sleep; and some people have had them at four in the morning after they have got up to go to the toilet, we could be inventing terms until the cows come home. 
Hypnagogia means not quite awake and not quite asleep and this trance like state can happen at all sorts of times of day - even at work. 

Observations

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