Space Wars. Extinction.

We do not currently know whether intelligence, biological or artificial, exists beyond Earth, but it is not implausible to assume so. Coming into contact with as well as refraining from seeking contact with extraterrestrial intelligence poses risks, as I discuss in section 4. In addition to these risks, extraterrestrial intelligence also poses a conflict risk: If an extraterrestrial intelligence has moral values that are sufficiently different form humankind’s, the intelligence could de facto react to humankind and other forms of intelligence with hostility.

At first glance, the prospect of a hostile extraterrestrial intelligence, be it biological or artificial, might seem far fetched. Isn’t some baseline of altruistic moral behavior to be expected of any kind of intelligence? We might intuitively associate intelligence with prosocial behavior of one kind or the other, but from an evolutionary perspective, greater intelligence is not necessarily correlated with prosocial and altruistic behavior towards other species [44]. Intelligence is the generalized capability for achieving goals, regardless of moral underpinnings and considerations. After all, that is why artificial intelligence as superintelligence is an existential risk today: Superintelligence is a threat precisely because it is much more intelligent than humans but lacks any inherent sense of human preferences and moral values.

Hostile extraterrestrial intelligence is a serious risk even if such intelligence is exceedingly rare in the universe. The mere possibility of hostile intelligence could result in something like a “Dark Forest” [45] game theoretic configuration. If benevolent biological or artificial intelligence is aware of the possibility of hostile alien intelligence, the best course of action is silence (If there might be hostile alien intelligence, best not to be noticed.). In addition, preventative action could also be a rational choice: If an alien intelligence — such as our human civilization — is being observed gradually expanding beyond our home planet, a risk averse intelligence, even one that is benevolent in principle, might find it prudent to eliminate that civilization; be it because the civilization in question might become hostile or because it might, through folly or ineptitude, draw unwanted attention to oneself. The mere possibility of fundamtenally hostile intelligence could, in that sense, be enough to fuel a silent astronomical war.