And "purpose" requires an understanding of intent. We need to find out, do they make conscious choices or is their motivation so instinctive that they don't understand a "why" question at all. And-And biggest of all, we need to have enough vocabulary with them that we understand their answer.
Louise Banks: The weapon is their language. They gave it all to us. Do you understand what that means?
Colonel Weber: So we can learn heptapod. If we survive.
Louise Banks: If you learn it, when you really learn it, you begin to perceive time the way that they do. So you can see what's to come. But time, it isn't the same for them. It's non-linear.