Wish You Were Here starts with an effect of distortion as if being played through an out of tune radio. This was deliberately installed by Roger Waters to signify the distance he felt from his audience. Upon entering the studio the whole band felt they were giving its best and couldn't identify why.
The whole album it was taken from was dealing with feelings of detachment. The famous cover of two men in suits shaking hands while one is on fire was an attempt to convey its theme.
Syd Barrett had allegedly having his coffee laced with LSD by a `friend' and Roger Waters says that this song is an extended version of a poem he wrote about Barretts losing grip on reality.
Dave Gilmour said in an interview once "If every one interpreted the same meaning from a song that he had written, then he had failed miserably in his endeavor". His philosophy to writing was shown well in such a universal theme that is dealt with by `Wish You Were Here'.
It is essentially a song about people detaching from reality and how they deal with loss, loss of themselves and loss of others.
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