Stairway to Heaven

I have checked out both links, thanks. My personal opinion is that both sources are dubious, but the best way to find out is to actually get a copy of a sound file and reverse it and listen yourself.

would like you to try this:
Backmasking
On this site are 12 songs, with the forward and backward versions, including Stairway to Heaven.

Listen to each on of them backwards, without clicking on the "show reverse lyrics" first. Listen before clicking, and write down whatever u think u are hearing. After that click on the lyrics and listen again.
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(Assuming that the guy never dong4 shou2 jiao3 with the clips) I tried the above, and I got zero out of zero correct. All I heard was rubbish. Then I listened again, this time turning on the lyrics. This time it seemed to make sense. The question is, why was I unable to hear the "correct" lyrics beforehand?

This is where my opinion might differ from your one: I believe that the mind makes sense out of what it sees or hears, based heavily on context / experience. Perception is not absolute (no right or wrong.) I.e. u draw a triangle on a piece of paper, erase the three vertexes. Ask people what they see, I think more will say "triangle" instead of "3 straight lines".

I think there is one way to test it. If what I say is true, then it is possible to find another set of words that sound equally "correct" to people, i.e. matches what they hear.

If what I say is false, then no matter how hard I search I can never find another set of lyrics that convincingly matches the reverse playback. i.e. only the Satan 666 version will sound correct.

Get 20 people who have never heard Stairway to Heaven, split them into 2 groups, set the null and alternative hypotheses as above. One group sees the Satan lyrics, the other sees the alternative. Compare the 2 groups. If I am ever boh liao enough one day, I will try to conduct this experiment. Get an additional 10 people and ask them to write down what they hear without looking at the supposed lyrics.

My personal experience with the Stairway to Heaven song is that when I listened to the reverse again later without looking at the lyrics I realised I had forgotten most of the lyrics. i.e. they don't make sense to me.

Hmm. In fact if my hypothesis really is correct, it has other applications e.g. why people believe in astrology etc-->concerning the suggestibility of humans. Hey, thanks for giving me idea for FYP, shiok!