Why Is It That Only Human Beings Produce Hamlet?

I would hesitate to recommend that people assume that a materialistic explanation ought always be favored. There's this idea which I think is what you're describing as scientism here. But explaining human action in terms of an ultimate sense of spirituality and belief in God is a powerful explanation. And so when we ask, why is it that only human beings produce things like hamlet? It may be because engaging in artLike this is a way to escape death in the sense of having something of yourself that outlast your physical death.