For all the discussion Facebook has prompted, its most profound impact may be to alter, even obliterate, conventional notions of the past, to change the way young people become adults.
As a survivor of the postage-stamp era, college was my big chance to doff the roles in my family and community that I had outgrown, to reinvent myself, to get busy with the embarrassing, exciting, muddy, wonderful work of creating an adult identity. Can you really do that with your 450 closest friends watching, all tweeting to affirm ad nauseam your present self?
The very thing that attracts us oldsters to Facebook — the lure of auld lang syne — will be its undoing.