<wob_jonas> perl -eopen$i,"<",($f="wisdom/aristotle");$_=<$i>; s/(fifth) kind of vitreous/$1/ or die; if (1) { open$o,">",$f; print$o $_ or die; } print substr$_,200;

To nvert something is to revert it back to its previous form, while recording the reversion as a conversion in itself.