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Re: on the nature of trust

Ben Laurie wrote:
> Marc Branchaud wrote:
> > Without some externally transmitted trust, what we have is a kind of Turing
> > test for trust -- is it really Ed, or just an incredible simulation?  This
> > might be an easy question to answer in a trivial context, but I think that an
> > external trust channel would be needed in a situation of any significance.
> But isn't this the essence of trust? No-one can devise a protocol that
> will make me trust things, can they? This "external trust channel" can
> only exist if I trust it. And will that trust come from an "external
> external trust channel trust channel"? I think not.

What you're suggesting is a Zeno's paradox of trust -- no matter how close you
get to trusting something, you'll only ever be haflway there.  So how does one
come to trust anything, then?  How can we ever trust a bank to keep our money

One answer is that we can never fully trust anything.  But banks are
successful because at some point a depositor decides that the bank is
trustworthy enough.  That decision is based on information from different
sources -- the bank, the government, family, friends -- each communicating
over a different channel.

The point of Ed's definition, I believe, is that you can trust a transaction
with your bank's ATM because you've received enough other information over
other channels & from other sources (e.g. you got your bank card from a bank

The same paradigm applies to online messaging: you trust a message because
you've received enough other information in some external way.


 Marc Branchaud                                       \/
 Chief PKI Architect                                  /\CERT SOFTWARE INC.
 marcnarc@xcert.com        PKI References page:              www.xcert.com
 604-640-6210x227      www.xcert.com/~marcnarc/PKI/

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