To mark Halloween, I hereby endorse mild regulation to discourage the summoning of dark supernatural powers which might destroy us all. Seriously. Anders Sandberg:

The San Marino scale for assessing the significance of messages that could be received by aliens … is a scale from 1 to 10 based on how easily detected the transmission is, and how much information about humanity it contains. Past deliberate transmissions have managed to reach 8, ‘far reaching’. Even planetary radar manages to reach a level of 6, ‘noteworthy’.

So, how far does these [recent] advertisements go? The Deep Space Communications dish is apparently 5 meter in diameter … The Dwingeloo telescope used for the Klingon invitation is a bit larger, 25 meters, but again the transmission power is unclear. … The level 8 signal from the Arecibo used about half a million Watts of power, making it far more powerful than anything these telescopes can achieve. … It hence seems that compared to past messages these adverts are unlikely to matter: we are already transmitting other messages, these just add to the choir. …

How much should small groups of people be allowed to risk the future of humanity with low probability? Not everyone agrees that the risk from alien contact is negligible: even a very low probability times a great harm can be relevant. … Should we be equally concerned with occultists trying to summon world-changing supernatural powers? There are probably many more people today who believe in supernatural entities than mere aliens, and that some interactions with them could be harmful. Yet there are no attempts at formulating risk scales for ritual magic. … Even if we were to analyse them rationally, we need to have an ‘ultraviolet cut-off’ for the infinite number of possible-yet-exceedingly-unlikely possibilities we could worry about. How to rationally decide on this cut-off seems problematic.

Even if the risk from recent ads is only 1/1000 of the risk of other prior transmissions, since I’m not sure how big was their risk I’m reluctant to conclude that the smaller ones are “unlikely to matter.” Perhaps 1/1000 of a bigger risk is still big enough to matter. So I’d support mild regulation to discourage such transmissions, big and small.

On which risks should matter, I’d prefer to use odds from a prediction market to decide. And my guess is that they’d give non-trivial (well over one in a million) odds both that our transmissions might alert hostile aliens, and that one could “summon world-changing supernatural powers.” So I’d also support mild regulation to discourage actions that might risk our descruction by terrible supernatural dark lords. Perhaps that sounds silly, but to disagree you either have to support our destruction by dark powers, or disagree that policy should be based on market odds.

Added 1Nov: Many of you talk as if one would have to go through a phone-book length list of potential disasters before one came to this one.  But surely this is one of the top ten disasters of concern in fiction, and would be similarly high in surveys.  Yes, you might not take it seriously, but others clearly do. The question is: what probability to use in policy when people disagree on probabilities. Surely the right answer is some sort of weighed average of opinion, and while willingness to bet is a great way to weight opinions, surely most any neutral approach will give a high enough probability of disaster here to justify substantial concern.  And this justifies “mild” regulation, which looks for the easy wins of large harm reduction at low cost.  Now it might turn out that there just don’t exist any feasible mild regulations, but we should at least consider some options before drawing that conclusion.