An admirer of humanists Shih once mentioned that he most admired the theory of the Japanese humanists Tenko Nishida and Kagawa Toyohiko. These were contemporaries of Shih, Japanese humanists who perhaps had a big impact on him.
施乾著作曾提及他最心儀日本西田天香及賀川豐彥等人的學說，這兩人正是與施乾同時代的人道主義者，可能對施乾有所影響。