How would intelligent aliens think? Would they have conscious experiences? Would it feel a certain way to be an alien? It is easy to dismiss these questions as too speculative, since we haven't encountered aliens, at least as far as we know. And in conceiving of alien minds we do so from within – from inside the vantage point of the sensory experiences and thinking patterns characteristic of our species. At best, we anthropomorphize; at worst, we risk stupendous failures of the imagination.

Still, ignoring these questions could be a grave mistake. Some proponents of the search for extraterrestrial intelligence (SETI) estimate that we will encounter alien intelligence within the next several decades. Even if you hold a more conservative estimate – say, that the chance of encountering alien intelligence in the next 50 years is 5 percent – the stakes for our species are high. Knowing that we are not alone in the universe would be a profound realization, and contact with an alien civilization could produce amazing technological innovations and cultural insights. It thus can be valuable to consider these questions, albeit with the goal of introducing possible routes to answering them, rather than producing definitive answers. So, let us ask: how might aliens think? And, would they be conscious? Believe it or not, we can say something concrete in response to both of these questions, drawing from work in philosophy and cognitive science.

You might think the second question is odd. After all, if aliens have sophisticated enough mental lives to be intelligent, wouldn't they be conscious? The far more intriguing question is: what would the quality of their consciousness be like? This would be putting the cart before the horse, however, since I do not believe that most advanced alien civilizations will be biological. The most sophisticated civilizations will be postbiological, forms of artificial intelligence (AI). (Cirkovic and Bradbury 2006; Shostak 2009; Davies 2010, 153–168; Bradbury et al. 2011; Dick 2013). Further, alien civilizations will tend to be forms of superintelligence: intelligence that is able to exceed the best human-level intelligence in every field – social skills, general wisdom, scientific creativity, and so on (Kurzweil 2005, Schneider 2011a, Bostrom 2014). It is a substantive question whether superintelligent AI (SAI) could have conscious experiences; philosophers have vigorously debated just this question in the case of AI in general.