Louise Banks: Am I fired?Colonel Weber: You're better than the last guy.Louise Banks: That doesn't make me feel any better.
Come back to me.
Like their ship or their bodies, their written language has no forward or backward direction. Linguists call this "nonlinear orthography," which raises the question, "Is this how they think?"
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.