This article is the third in our series at presenting the main branches of philosophy as axiomatic theories. The reserch procss on social philosophy led us to present our results in two seperate parts: the axiomatic system of the general concept of social philosophy and the axiomatic sysem of the social philosophy of modernity (capitalism, socializm, and their convergence). Each of these two parts comprises its axioms, definitions, theorems, and proofs of theorems. The axiomatic form of bulding the theory appeared helpful for identifying the main innati social features of modern man. This study suggests also the formula for the optimal organization of modern society.