imagination and in plausibility according to our current understanding of science. However, the scenarios considered here are limited to those that: are self inflicted (and therefore imply the development of intelligence and sufficient technology); technologically plausible (even if the technology does not currently exist); and that totally eliminate the (in the test case) human civilisation. Baah. So they took a look at the last three cofactors of Drake's Wild Guess, smoked a bowl and decided to strategize around a limited set of circumstances of those last three and write a paper about it. We are not impressed. If you're going to go full-on imaginary science, at least humor Hawking's notion of malevolent space beasties.The variety of potential apocalyptic scenarios are essentially only limited in scope by