Campbell goes into great detail, explaining what it is that people are seeking, as well as the whys and hows. Trying to summarize it with a few posts on this thread would do great injustice to him and his work. Are you not at least interested enough to look at Campbell's work yourself and offer a personal observation?
edit: Youtube has dozens, maybe hundreds of clips with Campbell. Some are as short as 3-4 minutes. The ones with Bill Moyer are especially good.