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but facilitates the transfer of its metabolites to the light cells.
In real organisms, a similar function is fulfilled by the cells of the
heart distributing blood throughout the body of an animal. Such a
modification would not directly benefit the dark cells as individual
cells, but would, on the other hand, promote the growth of the
light cells and consequently that of the heap of cells as a whole.
The dark cells would thus benefit indirectly. Their growth would
be optimised as cells belonging to an organised set. The variation
in the structure of the cell giving rise to this transformation would
be selected because it is favourable to the whole of the population.
This model provides us therefore with a general framework for
understanding, without finalism, the appearance of functions which
improve the performances of the organism as a total individual
entity. It provides an explanation for Bernard's belief in which he
asserted that “ The actual role of organs is not the agent that has
caused their formation ” (LPL p. 243). This antifinalism of Bernard's,
to which we wholly subscribe, goes even further since it results in
depriving the notion of function of any objective value, and in its
complete 'de-essentialisation'.
“Apart from the intervention of the mind, and insofar as there is
objective reality, there is in the organism only a multitude of acts,
of material phenomena, simultaneous or successive, dispersed
among all the elements. It is the mind that grasps or establishes
their interconnections and their relationships, that is to say, their
function. Function is thus something abstract which is not repre-
sented materially in any of the properties of the elements” (LPL,
pp. 268-269).
6.2
The deterministic theory of cell differentiation
We can now return in more detail to the question of cell differenti-
ation, which we looked at earlier but at a very general level.
Although embryogenesis cannot be reduced exclusively to this
process, it is one of its main aspects. The problem it poses is in
understanding how differentiated cells are produced from a single
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