william(at) william at
Tue Mar 15 23:32:10 UTC 2005

On Tue, 15 Mar 2005, Paul Vixie wrote:

>>> If it *actually* worked right, why do I *ever* encounter people that
>>> don't even know what block lists they're using?
> As MAPS found out during some early legal imbroglios, it is very easy to
> convince a judge that at least one ISP has subscribed to a blackhole list
> without understanding the full effects that this choice would produce.
> The whole "click to agree" (or "press F8 after scrolling to the last page")
> thing from software vendors is no better.  There's no way a judge (nor, one
> assumes, a jury) will ever believe that everyone who signalled agreement,
> understood.  The last couple of times I've signed closing papers for a
> house I've had to write several times "I agree, and I understand english"
> longhand and then sign my name -- but I don't think that'd hold up to a
> challenge of nonunderstanding, either.

Mortgage agreement is not the best choice for comparison on how blocklists
are used, its slightly different concept.

Blocklist use is example of delegating responsibility which is common and 
rooted in our political system (and concept is in use both by government 
and private businesses). Since one person can not possibly make a decision
about each and every detail of their life (although libertarians claim 
otherwise) we choose to delegate responsibility for certain tasks to certain
other people or organization that specialize in those areas. This is both
more manageable and as far as overall costs are concerned.

By delegating the task we accept the consequence that somebody else would 
be making decision on our behalf on this particular subject but this is 
done by choice and either each person participates in directly choosing 
who would be doing the decision or accepts decision make by majority 
social group he's in or delegates making decision on who would be doing
involved to somebody else (delegation chain).

In terms of use of blocklists, the end-user directly delegates responsibility
for making decisions about which emails are good or bad to his ISP. In 
parcticular if user uses email with ISP's domain name than in fact ISP has 
full rights to make decisions about their domain and user has to accept it 
by default as he/she just buys partial use with that domain, but if user 
has his own domain, then he/she makes decisions by buying mail hosting 
service and delegating responsibility regarding how email is delivered 
has to be explicit as part of such mail hosting service agreement. Now 
ISP then delegates responsibility further by choosing select list of 
organizations they believe are better qualified to make decision if the 
source of the email is good or bad - these are blocklist operators, so
there exists delegation chain from end-user to blocklist operator
(just like there exist delegation chain about regulations regarding 
telecom services which we buy, thse regulations are made by FCC which
is in turn chosen by the government and approved by the parliment
to which end-users deligated this reponsibility by selecting it).

In each case by delegating responsibility you accept consequence that 
somebody else would make a decision and you have to live with such 
consequence, such as that those others may occasionally be wrong (and
if they are wrong too often you can be vocal about it and they either
change based on your comments or you make different choice). If you do
not like all this, feel free (with your own domain name) to not use
filtering service and make decision about every email by yourself, however 
the problem is that you'll spend more time on that  that you could be 
spending on something else more productive and as such this time in fact 
does cost you something even if it provides you better granularity and 
direct access to the decisions. At the same time by delegating responsibility
you accept (often free) service provide by blocklist and it is usually 
more cost-effective (both to each individual and definetly to society 
costs in general).

William Leibzon
Elan Networks
william at

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