This is an incredibly simple issue: If a tree falls in a forest and no one is around to hear it IT DOES NOT MAKE A SOUND since "sound" itself (by definition) is a psychological phenomena and REQUIRES a live recipient. Otherwise the tree simply creates waves in the immediate atmosphere.

Bill has thoroughly confused making a sound with hearing a sound. Sound is indeed a matter of pressure waves. Once made, the sound may or may not be heard, but the disturbance of the medium (in this case, air) has occurred and exists independently of any perception of it. Sound is a matter of perception to psychologists, audiologists, and such, but it certainly is not "by definition" a "psychological phenomena" (sic), and any physicist would be happy to point out the error of your conception. There are therefore two distinct uses of the term, with neither superior to the other. But of course, DZ is absolutely right.

More seriously, I'd finish the sentence by saying "then we will have to survey people who weren't even there to get their opinion of what they think they would have heard and felt had they been there"

The idea of social theorists discussing a tree falling in the forest is an interesting way to explore different perspectives. It makes you think about how we perceive things. Speaking of trees, if you need help maintaining your greenery, Tree Trimming Fullerton provides affordable and reliable services to keep your trees healthy and looking great in Southern California.