In the ancient Indian movement theory, all movements were epistemologically considered as momentary movements. Continuous movement was understood as a series of momentary movements caused by a volitional effort or a propulsive power. Momentary movements in the Indian movement theory are classified into five kinds. These are moving upwards, moving downwards, bending, stretching and going. This movement theory is described in the work, Prasastapadabhasya, written in the sixth century A.D. In this paper I would like to explain what kinds of movements these five momentary movements are (1); and consider the reason why these five movements were chosen as the fundamental kinds of movement (2). (1) The "going " is a movement in which the direction is not specified by volitional effort. The other four movements are movements in which the directions is determined in the vertical direction by a specific volitional effort. A number of movements were classified as the "going " kind of movement in the work, Prasastapadabhasya. In the Indian movement theory the direction of movement of matter in the transverse direction was not specified by a volitional effort, because in the transverse direction, matter could be moved in various directions through a volitional effort.(2) In the Indian movement theory, the momentary changes of place on the moved matter which were brought by the momentary movements of matter were considered as important attributes of movement. In this theory, the fundamental kinds of movements were recognized from an objective point of view. And from this viewpoint all movements were objectively classified into two kinds; the movement in which the direction was determined by a specific volitional effort and the movement in which the direction was not specified by volitional effort. Moreover, the determined direction of movement of matter was in the vertical direction objectively. It seems that the above five movements, namely, moving upwards, moving downwards, bending, stretching, and going, were chosen as the fundamental kinds of movements in the ancient Indian movement theory.
Seitaro Tsuboi, a professor of petrology at the Imperial University of Tokyo, played the central role in introducing Bowen's theory to the petrological community in Japan before World War II. Influenced by his predecessors, Tsuboi became interested in so called "new petrology " employing physicochemical methods. To Tsuboi, Bowen's theory was the most important amoung them. Based on both his uniquely developed optical method to examine minerals and his own research philosophy, he could add more details to Bowen's theory. Facts suggest that Tsuboi's study was received certain recognition in his days. However, it does not mean that Bowen's theory was either well accepted or deeply understood since such a "new petrology " was not necessary for the majority of researchers who employed traditional descriptive methods. Although no strong dislike to Bowen's theory came up, some petrologists felt somewhat uneasy about the research methods. Nevertheless, there were not serious controversies between Tsuboi and those scholars partly because their understanding the theory and physicochemical methods was not deep enough to develop effective criticisms and partly because the theory and Tsuboi's methods were not widely penetrated into the community. However, after World War II, serious controversies around the theory came up where Tsuboi was criticized as a man of formalism who neglected the observed facts. The fact was that Tsuboi actually always kept it in his mind that Bowen's theory was neither perfect nor absolutely true; therefore, he pursued the logical clarity between theoretically induced ideas and observed facts. These will be discussed in later papers.