Language has ghost words awaiting the necessity of invention, or that pre-exist before exciting new meanings. Consider the Brazilian language Pirahã. It has no colour words, only terms for bright and dark in general. Things are described using comparison (leaflike, sunlike) but with no fixed terms (green, yellow). Nature abhors a vacuum. Pirahã speakers refer every day to colours, but have no generic words for them. Colour evolution seems to come entirely from poetic naming of objects. Sitting in Australia in January, it’s hard to believe that ancient Chinese, Japanese, Greek, Hebrew had no word for blue. Let alone cerulean.