The article deals with the problem of certainty of legal cognition in the context of the evolution of Natural Law. It is noted that the category of certainty was understood differently by representatives of various scientific schools and strands of theoretical framework idea. However, the classical doctrines were similar in the sense that certainty is necessary as the initial principle of cognition of legal reality, in contrast to the relativistic post-classical theories, which took the diametrically opposite principle as a methodological basis, namely «uncertainty». The article actualizes the understanding that Nature Law as a classical type of legal understanding has an internal logic of development. It is noted that modern theories of «Resurgence of Natural Law» generally remain within the framework of natural law concepts, but still overcome the dualism and parallelism of the systems of natural and positive law. In ontology, the modern Natural Law recognizes the human construction of law, the participation of the subject in the constant reproduction of legal reality; in epistemology, it recognizes the inclusion of the subject in the process of cognition, the rejection of the absolutization of the «legislative» mind and the transition to an interpretive «communicative» mind; in axiology, it defends socio - cultural concretization, including in the current legal system. The authors actualize the idea of intersubjectivity of law as integrating various aspects of legal cognition and the operation of law, focusing on identifying the meaning of law not from the point of view of one - dimensional monosubjectivity (individual or homogeneous society), but in dialogical (polylogical) intersubjectivity - in the interaction of subjects of legal communication. Recognition of the dynamism of law, the actualization of law in law enforcement activities problematizes the idea of certainty in law, but on a new, human-centered methodological and theoretical basis.