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from all the potential structures (Fig. 15C), which is the most sta-
ble (or the most viable) in the environment where the molecules are
suspended. Because of the stochastic character of interactions
between molecules, this ontogenesis never completely ends, but con-
tinues indefinitely since dissociation and reassociation is always
taking place between the molecules, caused by thermal agitation.
As long as the selective constraint (the environment) remains the
same, the same structure continues to be selected. If the selective
constraint were to change (if the environment changed), random
interactions between the molecules would bring about modification
and adaptation to this new environment. However, due to the pre-
existing structure, the number of potential interactions i.e. the dif-
ferentiation potential, offered by the random set of molecules is
restricted. The structure is randomly modified, but not completely
reconstructed. One of its parts, its central core, is more stable
because it involves more interactions between the proteins, and
therefore more bonds to maintain its cohesion (Fig. 15, X). On the
other hand, random modifications are more frequent at the two
ends of the structure because there are not so many bonds to
stabilise it (Fig. 15D, D
′
, D
′′
). The range of possibilities depends
therefore on the state of the structure because the latter promotes
certain interactions between molecules and prevents others. We sug-
gest that in an actual cell its structure acts in a similar way. By
sorting non-specific molecular interactions, this structure ensures
its own maintenance and reproduction and also permits subsequent
differentiation because random molecular interactions are not com-
pletely eliminated. In our imaginary example, one of the potential
structures is selected (Fig. 15D) due to a new environment, and
each time the environment changes again, the structure is modified
within the framework permitted by its previous state and in line
with the same mode of operation (Fig. 15E).
In this context, the contradiction in genetic determinism is
resolved. The structure of the cell sorts random interactions
between molecules without being the product of them. It is the result
of a process that includes both stochastic molecular interaction and
selective constraint. The macroscopic state of the cell at a given
