As you probably know, the context of that line was talking about how he envied animals, so I believe "not one is respectable or unhappy over the entire earth" is talking about how animals do not take a specific animal and revere or revile it over others, as humans do with different figures in history or in... History is full of examples where people have hated other people, most often because they believed those people were greater than themselves or had power over them. Hating someone is an act of disrespect towards that person, meaning that everyone who has ever hated another human being must be unhappy. I hope you find this lesson helpful. Please let me know if you have any questions or comments about it.