In 2004, Mark Wegman, Peter Capek, Scott Fahlman, and I, wrote a paper about using charitable donations to “stamp” email messages as a mechanism against unwanted mass mailings (see Charity Begins at… your Mail Program (PDF)). The paper was not accepted at that year’s Conference on Email and Anti-Spam (CEAS).
In this year’s CEAS, Yahoo! presented a similar paper, profiling a micro-donation system that they’re piloting (see CentMail: Rate Limiting via Certiﬁed Micro-Donations (PDF)). Running code is always more compelling, and five years brings a change in focus.
The basic idea is that if you take a company’s or an individual’s existing donations, you can break them into small chunks of, say, one cent each, and count each of those chunks toward a “stamp” for your mail. On the theory that a spammer sending 50 million messages would not be willing to spend half a million dollars to stamp them, you can give at least some preference through your spam filtering to stamped mail.
MacGregor Campbell just wrote an article for New Scientist about Yahoo’s CentMail pilot, and he refers back to the IBM work and quotes Scott Fahlman and me (though he didn’t get the part that I’m not with IBM any more).
Here’s what he got from me:
Barry Leiba, also at IBM, points out that one of CentMail’s core features could also be a weakness, though.
People may not wish to receive messages plugging a cause they don’t agree with. “I might feel that by accepting his messages, I’m implicitly supporting his charity choices — choices that I might be vehemently against.”
I don’t think this is an insurmountable problem, but I don’t know how to get around it. Here’s the scenario in full, as I gave it to Mr Campbell:
I have a colleague whom I like and respect professionally, and with whom I get on well personally... except that we’re politically opposite. If we should start using Charity Seals or CentMail, I might feel that by accepting his messages, I’m implicitly supporting his charity choices — choices that I might be vehemently against.
Note that this issue exists whether or not we disclose the specific charities. The fact that I know what kind of organisations he’s likely to donate to is sufficient to trigger it. So we can’t mitigate this just by saying (as Yahoo! appears to be doing) that the message is stamped, without saying to what charity the sender gave money.
The responses I get to this concern are usually either
- “That won’t really be a problem,” which amounts to summary denial, or
- “We’ll only choose non-controversial charities,” which I think is somewhat naïve, and perhaps unworkable.
It might indeed be that it won’t turn out to be a problem. We won’t know that until it’s out there, and we see how it works. I worry, though, that if it does become a problem, it’ll be harder to solve at that point.
That said, I think the charitable donations thing is a good idea, worth pursuing, piloting, experimenting with. I’m eager to see how Yahoo’s program goes.