Arrival, and the Ted Chang story it's based on, take on the problem of communicating with a truly alien lifeform. Back in the real world, people have been communicating with ASL-signing great apes and talking parrots for decades, and debating about whether we are having an actual conversation for almost as long. So, why should we think we'll be able to converse with aliens, and what can we learn from bonobos, elephants and dolphins (among others)?