Platonic perfection and plastic saucers

How man came up with words and writing is a topic some find fascinating and no doubt part of that is the insoluble aspect to the question. But seeing the full moon, made me wonder if our planet had had no moon, would the lack of what seems a perfect sphere, in a world so obviously not, have resulted in our missing this -- a lack impossible to imagine, that we never made the evolutionary leap, to a cerebral stage.