we used maggots to deal with infections , we conducted medical operations without anesthetics . Now that we have the means to live without those operations , we doMaggots are used in some places as a good way to remove dead diseased tissue while leaving healthy tissue alone . There are also medical operations that are performed without anesthetic Angioplasties being one of them . Humans do best when constantly evolving and continuously improving the way we live . That ' s assuming that not eating meat is an evolved and ' improved ' way of life . Our distant ancestors were herbivores the common ancestor we share with Chimps for example , then became omnivores . It could be argued that going back to being herbivores is actually regressing not progressing .