On Sep 9, 2013, at 4:27 PM, Steve Crocker <steve@xxxxxxxxxxxx> wrote: > Actually, I interpret the chemistry professor's comment in a different light. It would be possible to design a system where: > > o the standard end user software doesn't facilitate editing the other person's text, and > > o each piece of text is signed. > > The result would be a system where a recipient would know whether the person who is alleged to have written a piece of the message actually did so, and the normal mode of use would be to leave things untouched. Or, if you edit someone else's text, it immediately becomes your text. That's what I assumed Brian was implying, yes. :)