The spectacle - exhilaration and humiliation all muddled together, on stage as in life - will appear at FringeArts Thursday through Dec. 13 in the form of The Sincerity Project. Then, if all goes as planned, it will return with the same cast every few years for the next 24 years. Like a live-theater version of the Up documentary films that have tracked a dozen British children since 1964 from age 7 to 56, it will, Torra hopes, capture the aging bodies, evolving relationships, and changing views of seven cast members whose ambitions, impulses, and fears provide content for the show.