© GettyA website dedicated to sharing survivors' near-death experience stories has revealed some incredible claims about the afterlife.
Problemet er selvfølgelig at de eneste mennesker som helt sikkert ved det, er døde...så de er ikke til megen gavn når det drejer sig om at udfylde hullerne [ i vores viden].
Men hvad med mennesker som dør og så kommer tilbage til livet - som del af en nær-dødsoplevelse?
En hjemmeside, Near Death Experience Research Foundation, har gjort det til deres mission at samle historier fra mennesker som kom tæt på døden - men levede til at fortælle deres historie.
På hjemmesiden har antagelige overlevende delt et væld af utrolige historier om hvad efterlivet virkeligt er, med nogle forbløffende påstande om livet efter døden.
Nogle af førstehåndsfortællingerne er uhyggelige, som den historie af en person som hævdede at have oplevet en vision af helvede under et selvmordsforsøg.
Kommentar: Denne artikel er delvis oversat til dansk af Sott.net fra: Website collects stories of near-death experiences
They said: "I remember feeling terrified. It was so dark and I could not see anything below me, so it was hard to figure out what was going on.
"As the Beings pulled me into their midst, it seemed squishy and wet, as well as dark and cold. Meanwhile, the Beings all around me were ripping and tearing at me.
"I was thinking that I didn't like this at all and wanted to go back."
Another sinister experience came from a Czech woman who reportedly had a near-death experience due to pneumonia.
The woman, named only as Hana P, said: "I had a vision of a grey area with many scattered boards and beams.
"At the top right is a circular light, which had an incredibly bright centre that was inviting me to enter. Suddenly I realised with horror that it was the transition between life and death.
"I said, 'I do not want to enter. I have not tried everything in my life.'"
But not every story was so unsettling.
Most near-death experience survivors reported a feeling of calm, peace and warmth as they are bathed in a bright light.
A man identified as Richard L shared a recent experience which took place after a seizure two months ago.
He said: "I felt no pain. I felt an unending love and a sense of peace as I kept floating towards the light."
Many accounts of the afterlife overlap, with repeated references to a bright light and euphoric feeling - as well as a tunnel.
Alexander S, who reportedly nearly died after being attacked, said: "I saw a very bright light almost like at the end of a tunnel. It made me so warm and happy.
"I could just the see clouds and then I heard voices in the background."
And heart-attack survivor Tom B said: " I felt very relaxed and peaceful. Everything was black and I had the feeling of being in a tunnel. Way off, in the distance at the end of the tunnel, I could see a bright light."
Meanwhile, Heidi C's account of her near-death experience after a heart attack echoes many of these accounts.
She said: "The light was the most beautiful white, golden light. I felt immense happiness, contentment, peace, warmth and love.
"The light was bubbly, sparkling and effervescent, like champagne. There are no words to really express or articulate how I felt or to describe the beautiful light and warmth that I was bathed in.
"The colours and feelings were a million times magnified."
Previously, we told how a man who had a near-death experience explained what happens to good and bad people after they die... from "fear and darkness" to "a tunnel of light."
We also told how a top British scientist claimed that we all have souls which can live on after our bodies die.
Kommentar: World's largest Near Death Experiences (NDEs) study published
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