What's the difference between Descartes' mediations and Aaron's writings? Ignoring the obvious, technology simply made them easier to read. They're avail. on his public website whereas Descartes' mediations are more commonly found in textbooks and reproductions of his originals.
Descartes probably isn't the best example because with one quick Google search, I found this: http://oregonstate.edu/instruct/phl302/texts/descartes/medit... Still, the principle remains true.