Society … characterized by three moments

Externalization
Objectivation
Internalization

Berger, Peter L. & Luckmann, Thomas (1966 / 1991). A Treatise in the Sociology of Knowledge. London: Penguin Books. S.149.

Since society exists as both objective and subjective reality, any adequate theoretical understanding of it must comprehend both these aspects. As we have already argued, these aspects receive their proper recognition if society is understood in terms of an ongoing dialectical process composed of the three moments of externalization, objectivation and internalization. As far as the societal phenomenon is concerned, these moments are not to be thought of as occurring in a temporal sequence. Rather society and each part of it are simultaneously characterized by these three moments, so that any analysis in terms of only one or two of them falls short. The same is true of the individual member of society, who simultaneously externalizes his own being into the social world and internalizes it as an objective reality. In other words, to be in society is to participate in its dialectic.