Paper short abstract:

This paper will examine how dichotomous concepts which geophysicists use are related with the components of their practice. The analysis will provide the vision of science as the practice to make differences between the boundaries of the dichotomies.

Paper long abstract:

This paper will examine how dichotomous concepts which geophysicists use (e.g. the earth's surface/interior, physical/empirical, model/observation, hypothesis/fact) are related with the components of their practice, such as figures, computer programs and observation networks.

The paper will describe the practice called "observation" and "modeling" in geodesy, a sub-discipline of geophysics. Observational networks are deployed on the earth's surface. They provide the data which provide many kinds of figures. The figures generate the geodetic visible world and enact the boundary between the visible and the invisible.

Modeling process moves the boundary between the visible and the invisible. In modeling process, geodesists make computer programs and add the graphical expressions of the Earth's interior onto the figures created by observational data. At first, graphical expressions created by observational data are thought to be "factual", whereas those created by computer programs are "hypothetical". But the figures function as the interface of them because both of them take the same form of expression and then are comparable. Geodesists have various techniques to compare them and they moves the boundary between the factual and the hypothetical. Through these processes, geodesists make the factual visibilities of the Earth's interior.

The analysis will provide the unique vision of science: the practice to make various differences between the boundaries of the dichotomies.