The present paper is intended to expose an example of similarity in chemistry and in painting not based on shape or common origin but rather on the concepts they involve. I partly wrote this text in the 1980s. I was then learning solid state chemistry at the Weizmann Institute in Israel. At that time, it became evident to me that there was a possible link between a reaction in the crystalline state and one of the many interpretations of Las Meninas of Velázquez. More precisely, I asked myself if a relation might be found between an organic reaction in a crystal governed by the topochemical principle and the interpretation given by the French philosopher, Michel Foucauld, in his book The Order of Things, of Las Meninas in terms of the topology the gazes of the depicted figures.