This article discusses some aspects of the philosophical doctrine of academician Alexander Sergeyevich LappoDanilevsky (1863 1919), which is reflected, above all, in his "Methodology of History." Based on the philosophy of positivism and neokantian LappoDanilevsky tried to develop a theory of social science. One of the main principles of the methodology of the history of LappoDanilevsky considered the principle of the stranger spiritual life. Recognition of a stranger spiritual life advocated for LappoDanilevsky as a moral postulate necessary for understanding of social reality.