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’.