Ours is a resilient species. Around 70,000 years ago our total population may have fallen to between three and ten thousand individuals, possibly due to a supervolcanic eruption (Ambrose 1998) . Yet our ancestors survived, squeezed through the bottleneck, and flourished. But this resilience cannot be taken for granted. We are interconnected and interdependent as never before; the power and scale of our technological capacities are unprecedented. We are in uncharted waters and thus our previous survival is no longer a reason to expect our continued survival (Bostrom 2013). As a result, it is urgent that we develop a systematic understanding of the nature and causes of catastrophic and existential risks.