The paper is devoted to the discussion of the fundamental ideas of one of the most well-known French philosopher -Jacques Maritain concerning the problems of personalization and pluralism in modern democratic society. Exceptional actuality of the Maritain's treatment of the problems of the relations between laic state and believes for modern democratic countries social field are the quintessence of the paper. The fundamental questions of the philosophy of law: personalism and pluralism in the light of the concepts and interpretations of one of the brightest representatives of the French philosophical and law schools