Hmmm Jefferson in those letters was specifically talking about patents, not copyright. I don't think that Jefferson said much at all about copyright, as an inventor he stuck to patents which he thought were justified as they benefited society, but rewrite Jefferson if you must. In any case I seem to recall that a patent lasts for 20 years which is an increase of 6 years in the last 220+ years. and patents as far as I recall were NOT part of SOPA.