What distinguishes the types of umpires is not the situations in which they find themselves, but the attitudes that they bring to their work. As a result of those attitudes, they practice umpiring differently. Philosophers might identify the umpires' different claims as realism, contextualism, and social constructivism. Realism corresponds to the traditional view of science that links reality directly to observation. Contextualism suggests that how one looks at things will determine, to some extent, what one sees.
Social constructivism corresponds to the postmodern view, linking reality with power.
Discovery begins within the context of prevailing scientific beliefs. At the same time, the goals of discovery assume that previous knowledge is incomplete or wrong. Discovery takes place at the edge of knowledge, an ambiguous place where no one has been before. That description of research contrasts sharply with the traditional idea that in science, one proceeds from hypothesis to discovery in a linear fashion, guided by method and logic. Of course, some science does conform to that traditional model.