Humans observe animal behavior and come up with hypotheses that become theories that become facts (or not). Some behaviors can only be described as a series of actions for their intents and goals cannot be discerned. What would other self-aware, intelligent lifeforms out there say about human dance? Would they go for the mating-ritual explanation or would they come up with self-expression (provided they had some form of dancing too)?
Of all the pondering and believing I do about ideas or truths, intelligent alien species is not something I fully accept or reject. I’m undecided.