The practice of physics is shaped by experiences and expectations. Physicists and philosophers of science alike are tempted to evaluate scientific achievements by relating them to successfully tested predictions. However, some contemporary research programs at the physical frontiers refuse to be rated based on their power to predict testable phenomena. Without the crucial link to the natural world other criteria of evaluation must be considered. Recently, a shift of strategies for theory assessment was proposed as an explanation to why large numbers of physicists are attracted by string research. However, historical accounts have already indicated shifting practices of theoretical physics including string theoretical research.
This talk is based on a freshly finished MA thesis.