Some graduates were not enthusiastic about the first year of their training. For example, Paul von Hindenburg thought that the history of ancient battles should be minimized to give more time to modern, and that trigonometry was only useful to those who would be surveyors. The final two years satisfied him. While at the academy he was invited into the social circle of Prince Alexander of Prussia, where he came "in touch with men of science as well as those in the state and court service.