The $adult keyword should be removed from this draft on the grounds that the
definition is too vague to provide any value for interoperability. The
mechanism is inappropriate as the rules for what constitutes adult content
varies significantly by country, state, city, religion and culture (not to
mention the rules for what constitutes an adult). Thus it is not sufficiently
i18n-aware and I do not believe it can be made so.
Furthermore, it is controversial on ethical grounds as it provides a mechanism
for inappropriate censorship. Such mechanisms inevitably censor valuable
material such as discussion of "safer sex", "breast cancer", "nudity in art" or
similar topics which many believe should not be restricted to adults.
Finally, I can not see any technical way to correct all of the problems with
$adult. It must be removed from the draft.
Note that similar issues apply to the $Spam keyword but I believe they can be
corrected. As the definition of the term "spam" is controversial, I recommend
using the term "junk" which can more easily be defined as we wish. I would use
four keywords: $Junk, $NoJunk, $AutoJunk, $AutoNoJunk. "Junk" is defined as an
explicit end-user indication they do not wish to read similar messages in the
future. "AutoJunk" is an automated system's guess that the end user might
consider that message Junk. As $AutoJunk and $AutoNoJunk are error-prone, an
MUA MUST provide the ability to view $AutoJunk messages with reasonable
convenience.
This allows the combination "$NoJunk" and "$AutoJunk" which indicates the
automated system made a false-positive (very useful information to retain).
Now if present use of $Junk and $NoJunk conflicts with these definitions, we
should select new names which do not conflict.
- Chris
