Cosmic Irony: SETI Optimism from Catastrophes?

Classical arguments for skepticism regarding the Search for ExtraTerrestrial Intelligence (SETI) are critically examined. It is suggested that the emerging class of “phase transition” astrobiological models can simultaneously account for all available astrophysical and biological evidence, explain several unresolved puzzle in Earth sciences, and rationally justify current and future SETI projects. In particular, the hypothesis of Annis that local gamma-ray bursts drive the astrobiological phase transition deserves to be further quantitatively elucidated. Some epistemological and ethical ramifications of such a model are briefly discussed.