Abstract

Descriptive realism holds that T is true, while normative realism holds that T is warranted. Descriptive pessimism holds that T is false, while normative pessimism holds that T is unwarranted. We should distinguish between descriptive and normative realism because some arguments against scientific realism require that scientific realism be interpreted as descriptive realism, and because scientific realists can retreat from descriptive to normative realism when descriptive realism is under attack. We should also distinguish between descriptive and normative pessimism because some arguments against scientific pessimism require that it be interpreted as descriptive pessimism, and because scientific pessimists can retreat from descriptive to normative pessimism when descriptive pessimism is under attack.