es progress by failing in
consecutiveness and persistence. This is the condition of children and
barbarians, in whom instinct has learned nothing from experience. In a
second stage men are docile to events, plastic to new habits and
suggestions, yet able to graft them on original instincts, which they
thus bring to fuller satisfaction. This is the plane of manhood and
true progress. Last comes a stage when retentiveness is exhausted and
all that happens is at once forgotten; a vain, because unpractical,
repetition of the past takes the place of plasticity and fertile
readaptation. In a moving world readaptation is the price of longevity.
The hard shell, far from protecting the vital principle, condemns it to
die down slowly and be gradually chilled; immortality in such a case
must have been secured earlier, by giving birth to a generation plastic
to the contemporary world and able to retain its lessons. Thus old age
is as forgetful as youth, and more incorrigible; it displays the same
inattentiveness to conditions; its memory becomes self-repeating and
degenerates into an instinctive reaction, like a bird's chirp.

[Sidenote: Limits of variation. Spirit a heritage.]

Not all readaptation, however, is progress, for ideal identity must not
be lost. The Latin language did not progress when it passed into
Italian. It died. Its amiable heirs may console us for its departure,
but do not remove the fact that their parent is extinct. So every
individual, nation, and religion has its limit of adaptation; so long as
the increment it receives is digestible, so long as the organisation
already attained is extended and elaborated without being surrendered,
growth goes on; but when the foundation itself shifts, when what is
gained at the periphery is lost at the centre, the flux appears again
and progress is not real. Thus a succession of generations or languages
or religions constitutes no progress unless some ideal present at the
beginning is transmitted to the end and reaches a better expression
there; without this stability at the core no common standard exists and
all comparison of value with value must be external and arbitrary.
Retentiveness, we must repeat, is the condition of progress.

The variation human nature is open to is not, then, variation in any
direction. There are transformations that would destroy it. So long as
it endures it must retain all that constitutes it now, all that it has
so far gathered and worked in