Conversation so far:
what was revolvers background?
In December 1965, the Beatles' Rubber Soul album was released to wide critical acclaim.
how did the album do?
the limits of pop music "had been raised into the stratosphere" by the release.
what was the albums best award?
CANNOTANSWER.
what is the most important fact stated in this article?
Music journalist Carol Clerk describes Revolver as having been "decisively informed by acid", following John Lennon and George Harrison's continued experimentation with the drug LSD.
Are there any other interesting aspects about this article?
Despite his bandmates' urging, after Ringo Starr had also partaken of the drug, Paul McCartney refused to try LSD.
why did he refuse?
CANNOTANSWER.

Question: what did he do after refusing?
Self-contained rewrite: What did Paul McCartney do after refusing to try LSD?