Individual. Atom, Cell

A defining characteristic of an Atom, in the purest sense, is that it is essentially discrete with respect to its surroundings, a property formulated by Atomists as the 'externality of relations', which entails that an Atom remains unchanged by a relocation.  Thus, insofar as a Soul survives the death of a body that it inhabits, it is an Atom, as are a Capitalist Individual and Private Property, i. e. because of their independence from the rest of a society.  In contrast, a Cell is separated from its surroundings by a permeable membrane, i. e. a medium of interaction, which means that it is essentially of that location.  Now, the contingency, in Marxism, of an Individual with respect to their environment, is an indication of a repudiation of Atomism.  However, it is unclear if it goes further and accepts the Cellular concept of the Individual.  For, that concept entails permeability, and, hence, an interpenetration of Individual and environment, whereas Dialectical Materialism entails only their interaction, which can transpire merely in between them.  So, Marxism can be interpreted as constituting a partial transition from Physicism to Biologism.