In 1903, the San Diego Marine Biological Association was founded. This institution, which was to become the Scripps Institution of Oceanography in 1925, was one of the ordinary marine biological stations of the era. The founder and director of the Association, William E. Ritter, professor of zoology at the University of California, visited San Diego every summer with his colleagues and students to collect and study local marine organisms. How, then, did this marine biological station turn into an oceanographic institution? The seed for change lay in Ritter’s research program and his philosophical thought behind it. Unlike most other biologists of the time, Ritter thought marine biology had to take into consideration the fact that marine organisms live in the ocean. He distinguished the true marine biology from general biology using marine organisms merely as research objects without any consideration of their being ‘marine.’ Ritter’s program thus emphasized the influence of the physical environment of the sea on the lives of marine animals and plants. He also emphasized the importance of fieldwork and the use of mathematical and statistical methods. Ritter’s program of ecological marine biology can be seen as a reaction to the experimentalism in biology. He wanted to make marine biology a field science as much scientific as laboratory biology. On the other hand, the research program strongly reflects his holistic philosophy. Ritter argued for an “organismal conception of life” and thought that sum of parts can never be equal to the whole. Everything in a living organism is closely interrelated, and studying the relationship and interaction is the true purpose of biology. In the end, Ritter’s program was only a partial success. However, Ritter’s marine biology program was unique in that it aimed at the overall understanding of the marine life phenomena in connection with the physical marine environment. It was possible for T. Wayland Vaughan, who succeeded Ritter as the Institution’s director, to make the Scripps Institution truly oceanographic without much difficulty only because Ritter’s marine biology was already oceanographic in many respects.