of biology, long before the day of Darwin. The protagonist in this
case was the physician P.-J.-G. Cabanis (1737-1808), the colleague of
Laplace in the School of Sciences. Growing up in the generation of
the Revolution, Cabanis had met, in the salon of Madame Helvétius,
d'Holbach, Diderot, D'Alembert, Condorcet, Laplace, Condillac,
Volney, Franklin, and Jefferson, and became the physician of
Mirabeau. His treatise on the Rapports du physique et du morale de
l'homme (1796-1802) [1884] might be described as the systematic
application to psychology of that "positive" method to which all
the keenest thought of the eighteenth century had been tending,
yet with much of the literary or rhetorical tone by which the French
writers of that age had nearly all been characterized. For Cabanis,
the psychology of Helvétius and Condillac had been hampered by their
ignorance of physiology; [1885] and he easily put aside the primary
errors, such as the "equality of minds" and the entity of "the soul,"
which they took over from previous thinkers. His own work is on the
whole the most searching and original handling of the main problems
of psycho-physiology that had yet been achieved; and to this day its
suggestiveness has not been exhausted.
But Cabanis, in his turn, made the mistake of Helvétius and
Condillac. Not content with presenting the results of his study
in the province in which he was relatively master, he undertook
to reach ultimate truth in those of ethics and philosophy, in
which he was not so. In the preface to the Rapports he lays down
an emphatically agnostic conviction as to final causes: "ignorance
the most invincible," he declares, is all that is possible to man
on that issue. [1886] But not only does he in his main work freely
and loosely generalize on the phenomena of history and overleap the
ethical problem: he penned shortly before his death a Lettre sur les
causes premières, addressed to Fauriel, [1887] in which the aging
intelligence is seen reverting to à priori processes, and concluding
in favour of a "sort of stoic pantheism" [1888] with a balance towards
normal theism and a belief in immortality. The final doctrine did not
in the least affect the argument of the earlier, which was simply one
of positive science; but the clerical world, which had in the usual
fashion denounced the scientific doctrine, not on the score of any
attack by Cabanis upon religion, but because of its incompatibility
with the notion of the soul, naturally made much of the mystical,
[1889] and accorded its framer authority from that moment.
As for the conception of "vitalism" put forward in the Letter to
Fauriel by way of explanation of the phenomena of life, it is but
a reversion to the earlier doctrine of Stahl, of which Cabanis had
been a partisan in his youth. [1890] The fact remains that he gave an
enduring impulse to positive science, [1891] his own final vacillation
failing to arrest the employment of the method he had inherited and
improved. Most people know him solely through one misquotation, the
famous phrase that "the brain secretes thought as the liver secretes
bile." This is not only an imperfect statement of his doctrine: it
suppresses precisely the idea by which Cabanis differentiates from pure
"sensationalism." What he taught was that "impressions, reaching the
brain, set it in activity, as aliments reaching the stomach excite it
to a more abundant secretion of gastric juice.... The function proper
to the first is to perceive particular impressions, to attach to them
signs, to combine different impressions, to separate them, to draw from
them judgments and determinations, as the function of the second is to
act on nutritive substances," etc. [1892] It is after this statement
of the known processus, and after pointing out that there is as much
of pure inference in the one case as in the other, that he concludes:
"The brain in a manner digests impressions, and makes organically the
secretion of thought" and this conclusion, he points out, disposes of
the difficulty of those who "cannot conceive how judging, reasoning,
imagining, can ever be anything else than feeling. The difficulty
ceases when one recognizes, in these different operations, the action
of the brain upon the impressions which are passed on to it." The
doctrine is, in short, an elementary truth of psychological science,
as distinguished from the pseudo-science of the Ego considered as
an entity. To that pseudo-science Cabanis gave a vital wound; and
his derided formula is for true science to-day almost a truism. The
attacks made upon his doctrine in the next generation only served to
emphasize anew the eternal dilemma of theism. On the one hand his
final "vitalism" was repugnant to those who, on traditional lines,
insisted upon a distinction between "soul" and "vital force"; on
the other hand, those who sought to make a philosophic case for
theism against him made the usual plunge into pantheism, and were
reproached accordingly by the orthodox. [1893] All that remained was
the indisputable "positive" gain.