History of EQ (was: Re: [E-Lang] Progress & Non-Progress Report)

[Mark S. Miller]

At 06:07 AM Thursday 5/17/01, Tyler Close wrote:
>There seems to be an important historical omission on the "History of the Grant Matcher" page at:
>
>http://www.erights.org/elib/equality/grant-matcher/history.html
>[...]
>Let's update the history books before this one gets lost in the mist of time!

Good catch.  The end of this page now reads

>It's not so simple
>
>The thread rooted here <link to email archive> tells of Dean demonstrating 
>that the Grant Matcher puzzle can be solved with Sealer/Unsealer pairs 
>without EQ. Indeed, an EQ adequate to do grant matching can be built purely 
>out of Sealer/Unsealer pairs (and plausibly out of other rights 
>amplification primitives, like sibling communication). In Logical Secrets, 
>we had shown that Sealer/Unsealer pairs could be built (awkwardly) out of 
>EQ. So a capability system enhanced with either of these primitives is 
>adequate to build the other. My remaining hypothesis is that in a pure 
>capability system without either, one cannot build either. Dean (and 
>everyone else of course) is hereby challenged to demonstrate otherwise.


        Cheers,
        --MarkM