| Here
under follows the transcription of the chapter Descartes of
Houston Stewart Chamberlain's Immanuel Kant, published by John
Lane,
The Bodley Head, 1914. The note on p. 268 is by me, all
other notes are original.
DESCARTES
From the painting by Mignard,
from the Castle Howard Collection, now in the National Gallery.
|
195
DESCARTES
UNDERSTANDING AND SENSIBILITY
WITH AN EXCURSUS UPON ANALYTICAL GEOMETRY
Water is always like water,
but it has
a quite different
taste when drawn at the
fountain head from what it has
when drunk out of a pitcher.
Descartes.
196
(Blank page)
197
DESCARTES
THERE are days
and days, and I confess
that it is with some hesitation and distrust that I address myself
to-day
to the task of continuing our observations in common. For now I have to
travel with you through regions which it will not be so easy to make
clear
as it was so long as we had the eye of a Goethe and a Leonardo to
lighten
us on our way. The comparison with philosophers who were at the same
time
artists revealed to us much that was of fundamental importance, and
gave
rise to observations which could not but result in a deep insight into
the personality of Kant, in the narrower meaning of the word, but now
we
must face about, we must once more fix the lenses of our eyes upon a
nearer
focus; we must bring into comparison philosophers who in their turn
will
lead us far, but on another road; men, the atmosphere of whose lives
does
not consist in Beauty and Art, but in research and thought. To-day we
will
busy ourselves with Descartes the critically empirical, mathematical
thinker,
and in the next lecture with Bruno the logical schoolman and
enthusiastic
thinker.
You must
not
misunderstand me.
There is no such thing as an absolute artist, no such thing as an
absolute
mathematician, and above all no such thing as an absolute philosopher.
This sort of classification into professions will never succeed even
with
half-important men. Goethe and Leonardo were both of them, as we have
seen,
great investigators of nature, and thinkers:
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DESCARTES
Bruno and Descartes on
their side possess
in a pre-eminent degree the artistic gift of putting into shape: Bruno,
in
his manner of thinking and speaking, is as much a poet as Plato was;
and
Descartes, the masterful thinker, is so penetrated with the value of
perception
and the empirical investigation of nature, that he is the bitter enemy
of genuine professional philosophy. We, however, are dealing to-day
solely
with that which I should like to call the characteristic intellectual
attitude.
In Goethe and in Leonardo it is distinctly directed outwards: the
primacy
of the Eye is dominant in both, and indeed of the eye both as a
receptive
and reproductive machinery of the senses. It is true that we found the
result to be very different in the two men; for behind two equally
powerful
eyes two brains gifted in varying directions take up impressions, and
work
them up each in its own way. In Leonardo the gift of sight is more
precise
and, in the widest sense of the word, more correct in its perspective;
this he owes to the power, which we recognised in the previous lecture,
of referring all that he saw to the inner scheme of perception; before
Goethe's eyes, on the other hand, the outlines are uncertain, his power
of schematising is insufficient, and he mixes up his thought with
everything:
but it is exactly this which bestows on him the gift of illuminating
the
very depths of Nature, depths where without the lamp of creative
thought,
dark night reigns. Leonardo sees the relationship of things to one
another,
Goethe sees their relationship to the human intellect; in Leonardo's
understanding
the masculine element prevails, in Goethe's we find unmistakable
feminine
or receptive constituents; hence Leonardo's thought is keen,
mechanical,
scientific, and easily grasped, whereas Goethe's is deeper, more
iridescent,
baffling conception, because it is pregnant with presentiments too wild
to be tamed into words. We shall go further into this in a future
lecture;
for the moment
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DESCARTES
we must be contented with
recognising
the fact that this precise intellectual habit, the method of looking
outwards,
is the common property of both Leonardo and Goethe. At the same time
this
habit distinguishes both from Kant, even though a closer examination
has
revealed to us so many points of contact in the manner of Seeing
between
him, the artist in thought, and those two artist-sages. But now, for
the
sake of comparison, we will summon into court two men with essentially
different qualifications, — men whose innate intellectual habit points
inwards. I say “inwards“ because these thinkers in the first place
consult
their own thought, and only later on turn to Nature: they do not trust
the impression which comes from without, not, that is to say, until
they
have, as far as may be in any way possible, tested and dissected the
whole
details of the inner diagnosis: this method of procedure is the exact
opposite to that followed by Goethe and Leonardo. This habit I call the
method of looking inwards. René Descartes and Giordano Bruno
will,
as I think, answer our purpose: neither of the two is so nearly akin to
Kant as to prevent dark shadows being thrown upon the picture from them
upon him, and on the other hand, in respect of talent and feeling,
these
two great philosophers are just as fundamentally different from one
another
as Leonardo and Goethe. They have in common only — but this “only“
means
very much — the habit of the specific thinker. Bruno, the Goethe of our
second pair of philosophers, exclaims, Gli beni de la mente non
altronde
che dall' istessa mente rostra riportiamo 1 (it is from the mind itself
and from no other source that we acquire the riches of the mind), — and
Descartes,
the strict empiric, the Leonardo, says deliberately, Il n'est aucune
question
plus importante à résoudre que celle de savoir ce que
c'est
que la connaissance humaine, et jusqu'où elle s'étend,
... Rien ne me semble plus absurde que de discuter audacieusement sur
les
mystères de la nature sans
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DESCARTES
avoir une seule fois
cherché si
l'esprit humain peut atteindre jusque là. 2
These few words
will have sufficed
to show you with what manner of man we have to deal here; at the same
time
the patent relationship to Kant's objects and methods and convictions
is
at once striking. The investigation of the essence and of the limits of
human knowledge describes exactly a great part — the critical part — of
Kant's
Life-work, and that the peculiar riches of the mind must be acquired
from
within and not from without, puts into a few words what Kant looked
upon
as his positive, practical, and edifying achievement. But even the
points
of difference will teach us much. The life-stories of the seigneur du
Perron
(Descartes) and of the man of Nola (Bruno) show conclusively that these
two men as regards their intellectual talents are far removed from
Kant.
In the first lecture we saw how deeply rooted in Kant's method of
perception
and in his adoption of ideas was that peculiar feature which made him
so
painfully avoid even the shortest journey; Bruno and Descartes, on the
contrary, move restlessly from place to place, and from country to
country,
as the spirit moves them. Bruno, with his apostle's nature, needs new
contacts,
new excitements, new disputations; he is bound to strike sparks out of
life, to kindle flames in hearts; wherever he goes he arouses glowing
love
and irreconcilable hatred. Descartes, the reserved man of the world,
travels
in order to be alone, enjoys in cities “the solitude of the remotest
deserts,“
steals away from a place as soon as his presence is noticed, and at the
same time, by a systematic observation of the differently constituted
men
and nations, religions and customs, seeks to free himself from the
prejudices
which are rooted in us all. Je ne
fis autre chose que rouler ça
et là dans le monde, tâchant d'y être spectateur
plutôt
qu'acteur en toutes les comédies qui s'y jouent. 3 Such a funda-
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DESCARTES
mentally different
ordering of life points
to far-reaching differences in the essence of the intellect: we may
premise
without going further that Bruno and Descartes “saw“ otherwise than
Kant
did. This will be especially clear in the case of Bruno, who, in spite
of the purely philosophical tendency of his intellect, is in many
respects
the veriest antipodes of Kant, and as such can render us valuable
service,
whereas in Descartes the close kinship leads us to penetrate the inmost
secrets of Kant's method of perception, while allowing us to leave on
one
side the many points of difference between the two as having no value
for
the object which we have in view.
Among the very
great thinkers of
the world's history perhaps none has been so scurvily treated as
Descartes;
he,— I mean the true Descartes, — is as good as unknown; the shadowy
being
that under this name is represented to our imagination, is a mere
ghost-like
caricature. Here was a man who with desperate energy fought to purge
himself
and us of all philosophical phrases; whose burning endeavour it was to
tear philosophy out of the toils of a logic as arrogant as it was
impotent,
and to open its eyes to the one and only productive authority of pure
perception;
a man who in open and indignant opposition to the schools cried out,
“the
whole sum of human science consists in seeing distinctly“; — and of
this
man the vast majority of cultured people know neither the personality
nor
the life nor the achievements, with the exception of just one single
saying
which has been thrashed out until it has become a mere phrase — cogito,
ergo sum, — a mere jingle of syllables, unless we knew how it
originated
in Descartes, and whither it led him. Just think how it would be if
some
future history should have nothing more to report of Bismarck than that
his was the saying, “We Germans fear God, and nothing else in the
world,“
as if this very disputable
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DESCARTES
phrase represented the
sum-total of the
achievements of his richly active life! Where is the difference, if we
only take count of one ambiguous and much misunderstood saying of the
pioneer
in mathematics, the physicist, the anatomist, the kosmologist, the
philosopher,
of the man who perhaps more than any other has so enriched our treasure
of constructive imagination that to this day philosophy and science are
refreshed by the stimulants of his genius? But as though it were not
enough
that a philosophy resting upon the broadest foundation of an
all-embracing,
manifest consideration of nature, should have been to such an extent
turned
topsy-turvy by degradation into mere logical and psychological
nut-cracking
— beyond all this we are even robbed of the man's personality.
Descartes
was an aristocrat by birth, — by the bent of his intellect an extreme
individualist.
He does not only hold himself aloof from his fellow-men, choosing an
abode
in foreign parts, and leaving a town as soon as he becomes known and
gets
entangled in social relations, — but even intellectually he surrounds
himself
with a high wall lest the doctrines of the contemporary philosophical
guilds
should find their way in, and even for the time being digs a deep moat
to keep the wisdom of the ancients at a respectful distance. To treat
with
scorn the nullities of the professional philosophers — les bagatelles
d'école
— is for him the distinguishing mark of a “princely character,“ and of
himself he confesses, “not the understanding of the arguments of
others,
but personal investigation on my own account is what constitutes for me
the greatest happiness of study.“ It is in a quite different sense from
Schopenhauer that Descartes is a great Eremite; for in him there is
none
of the bitterness or vanity of solitude, it is a proud and peaceful
self-contentment.
It was only after long years that the incessant pressure of so
respected
a friend as Pater Mersenne determined him to publish, and it would have
203
DESCARTES
remained at that
fragmentary beginning,
had not the request of an exalted friend, the Countess Palatine
Elizabeth,
stood in the light of a royal command to so perfect a man of the world.
Je ne recherche point les bonnes
grâces de la populace, he writes
with quiet disdain in a private letter: but with him populace has a
wide
meaning; for when Mersenne communicates to him the criticisms of the
most
learned men in Paris, he answers, “I have long known that there are
asses
in the world, but I set so little store by their judgment, that it
would
vex me to be obliged to spend upon it even a minute of my leisure and
my
peace.“ No more is needed to show that an investigator who so
resolutely
follows his own road, and avoids all contact with the officially
recognised
masters of scholastic thought, will not easily develop a system of
philosophy
fitted to be formulated into a strict scholastic shape. The picture of
the world that Descartes unrolls before us, is no grafted scion such as
we are used to see in philosophy, but a tree grown from the seed. Plato
hangs upon Socrates, and also upon Pythagoras, Anaxagoras, Heraclitus,
and others: Aristotle springs from Plato; Bruno from Plotinus,
Lucretius,
Cusa; Locke, Berkeley, Spinoza, Leibniz from our Descartes; Kant, too,
springs from Descartes, and from Leibniz, Locke, Rousseau, Hume; and so
it is with all of them; Descartes alone stands by himself. And although
he is convinced of the truth of his perceptions, hoping that their
victory
will result in a new birth of the sciences, still he keeps such jealous
watch over his independence, he is so deeply concerned to be left even
after his death inviolate in his proud isolation, that he starts by
declaring
that his method is for himself alone, not for others; mon dessein n'est
pas d'enseigner la méthode que chacun doit suivre pour bien
conduire
sa raison, mais seulement de faire voir en quelle sorte j'ai
tâché
de conduire la mienne; — and so over and over again he does not
shirk
the
paradox
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DESCARTES
that his philosophy is
void of all originality,
which he only admits openly in order that the good people may not fall
into the idea of making his name the centre of a school. The idea was
to
him a scarecrow that there should come men who would imagine that they
could in a day compass that of which he had realised the insight after
twenty years of study and education, and that upon it they should build
up a Philosophy fit to make one's hair stand on end, should delude
themselves
into the notion that this Philosophy was the result of his “Principles,“ and
assure the world
that he, Descartes, was its founder. 4 It is touching to hear how
he
implores
posterity, — “never believe that the things of which people are
assuring
you sum up my teaching, and originate in me: ascribe to me only that
which
you gather from my own mouth“ — and his real wish, that is to say his
wish
in opposition to the founding of a school, he tells us clearly enough
in
the same passage, is ouvrir quelques
fenêtres, not to build up a
system, but to “tear open the windows and let in the light“ for all
those
who have eyes to see. You can now distinguish broadly, what occupied
this
great intellect, and what must needs be his aim when he at last allowed
himself to be talked over into appearing in public. Himself a free
personality,
who at the expense of great labour had torn from his eyes all the
bandages
which education, parentage, the wisdom of the schools, the doctrines of
the Church, had bound round them — his aim is to educate free
personalities,
and with that object not to teach them, — in the sense that is to say
of
the schools, — but to lure them on, and to do for them as he had done
for
himself, namely, to open their eyes, and make them teach themselves by
means of perception. By “philosophy“ he understands literally the
opening
of the eyes, oculos aperire. 5 And since this is the
fundamental
principle
of Descartes' personality and teaching, so he
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DESCARTES
cares nothing for the
fixed establishment
of great, universal, irrefutable principles, but gives himself a free
hand
in the intimate description of his often quaint ideas which only fit in
with his own personality. Only look at his portraits! look at his
innocently
amazed outlook over the world, and his slyly ironical smile at the
wisdom
of mankind! Why! the man is anti-scholastic to his finger-tips. Even
the
famous cogito, ergo sum (“I
think, therefore I am“) is no logical
conclusion,
at any rate for him, but the verbal expression, clothed accordingly in
the rags of logic, for a definite perception: and when the professional
schoolmen want to split hairs with him on the subject he winds up the
argument
by saying, “I do not argue the question of my being by a syllogism, but
I perceive it.“ 6
This
was the man
whose fate it
was to become — beyond the grave — the sacrifice of the populace in a
way
no other thinker did. Hardly was the breath out of his body when the
European
world of learning became divided into two camps, the Cartesians and the
anti-Cartesians. The proud Eye, so wise, so lovable in spite of all its
distrust, was closed; and now it was to be anatomically dissected and
lectured
upon. The teaching of Descartes, “perfected“ — as usual — by all manner
of
insignificant and contradictory minds, was transformed into a system of
scholastic definitions and rigid dogmas. Descartes had said, “as for
the
search after definitions, we can leave that to Messieurs les
Professeurs“;
in very many cases definitions only serve to make dark what is clear;
the
professor with his subtle distinctions clouds the natural light of the
understanding, and ends by making an obscure problem out of what every
peasant knows. Descartes had been indefatigable in confining logic
within
the narrow bounds of its justified effectiveness, since, as he says,
l'art
syllogistique ne sert en rien à la découverte de la
vérité;
whereas the art of logic is a
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DESCARTES
chief instrument of the
schoolmen for
talking of things about which they themselves know nothing. 7 A few
years
after his death there arose a complete logical system, the “Logique de
Port Royal,“ which pretended to be founded on his teaching. A very
short
time elapsed and this so-called Cartesianism was in the very centre of
the conflict over the Eucharist: Calvinists and Jansenists, the deniers
and the champions of the Real Presence of the Body and Blood of Christ
in the bread and wine, both appealed to Descartes: in his grave he was
marked as the founder of the philosophia
eucharistica; his loftily
plain
writings, conspicuous for their frankness, were forced to serve, like
the
arcana disciplinae of the
ancient mysteries, as evidence for and
against
the most abstract cobwebs of the brain, and between whiles the
Physicists
dragged out the over-hurried hypothesis of a genius on the Gyrations of
the Kosmos, fighting for and against it, as if the Personality and
nature-teaching
of Descartes must stand or fall by it; while Freethinkers and Pietists
both took possession of the so-called automatism of beasts, out of
which
they drew opposite conclusions. For more than a century the world was
filled
with the roaring of the Cartesians and the bellowing of the
anti-Cartesians;
of Descartes, the lonely investigator and thinker, there was no longer
any talk. And when at last, in no small measure out of seed which he
had
sown, a new science and a new philosophy had gradually grown up and
waxed
strong, universal contempt washed away the barren Cartesianism and the
equally barren anti-Cartesianism. The great personality of Descartes
had
long since faded away. Only the ill-starred cogito, ergo sum was
bandied
about like sea-wrack on the all-devouring ocean of the world's history.
True,
Descartes
receives honourable
mention in the philosophical histories. Schopenhauer's dictum, “the
Father
of the Modern Philosophy,“ has been universally
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DESCARTES
repeated; but it is
always in the sense
of what is called in stage language un
père noble, an honoured
but
not much noticed person of distinction in the background. I can
unhesitatingly
recommend to you the first volume of Kuno Fischer's comprehensive work
upon the modern philosophy: he gives at any rate a fairly exact
biographical
account of the man: but even here Descartes is so dealt with that he
falls
behind the other philosophers; and although there is much material
given
for a representation of his personality, this very representation, the
portrait of such a wholly individual intellect, the plastic bringing
into
evidence of his special significance, is a failure. In most of the
other
handbooks you will only find one chapter about him, entitled “Descartes
and his school,“ or simply “Cartesianism.“ He who said, “the great
intellects
talk nonsense as soon as it is their disciples who speak for them, for
it is perhaps outside all experience that any pupil should have
equalled
his master,“ that very man hardly exists any longer save in the title
for
a School! Nay, more: when all is said and done, few of our professional
philosophers are so equipped as to be capable of understanding the true
Descartes; for Descartes, as you will already have observed, is far
more
of a contemplator of nature than a philosopher in the scholastic and
still
authoritative meaning of the word:
indeed we might
frankly
call him an
anti-philosopher. For him philosophy, — this is his own literal
definition —
is a tree, “the golden tree of life“; its metaphysical roots strike
into
the dark earth, and as Descartes humorously remarks, it is not upon
roots
that fruit usually grows; the mighty stem is the science of physics,
under
which he comprehends the universal laws of all motion, and this stem
branches
off into the many empirical ramifications of knowledge, at the points
of
which flowers at last bloom, and the blessing of fruit ripens. 8 You
need
only look at Descartes' chief systematic work, the
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DESCARTES
Principles of Philosophy.
In Cousin's
edition the first part, which contains all the psychological and
metaphysical
discussions, needs only 57 pages; the three remaining parts, — Physics,
Kosmology,
and Geognosis, upwards of 400 pages, — while Descartes apologises for
not
yet being able to publish his Zoology, Botany, and Anthropology. He
indeed
was the first to put the problem of perception in the foreground, a
fact
wittily put by Fontenelle in the remark that, avant M. Descartes, on
raisonnait
plus commodément; les siècles passés sont bien
heureux
de ne pas avoir eu cet homme là; 9 and so he was the first man
to
awaken true metaphysical reflection; yet he himself spends but little
time
over it. It was the distinct perception of his own inner being that
served
him as the first step towards distinctness in the perception of visible
Nature. In the same way he made use of metaphysics as an active help to
physics. Anybody who is not competent to follow him in the domain of
natural
science and mathematics will find it difficult to do him justice. He
studies
the functions of his brain as a part of the world which directly
concerns
him, and is therefore of fundamental importance, certainly not in the
sense
of a professed philosopher in the ordinary modern meaning of the word,
whose calling and business it is to think over all matters in the
abstract.
He has no faith in the professional philosophy: he characterises it as
une grande erreur, and says, il est plus facile d'apprendre toutes les
sciences à la fois que d'en détacher une seule. A
man of this
stamp
is far removed from our philosophical professors, not only further than
their own dearly beloved Spinoza, who never once leaves the domain of
the
abstract, but further even than a Francis Bacon, who, it is true,
constructs
a Novum organum for the
dissemination of the knowledge of nature,
without
having ever himself been busied with mathematical and
natural-scientific
work, and whose first principle it is to
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DESCARTES
abandon all philosophy in
favour of a
so-called empiricism; 10
further too than a Locke, or a Berkeley, or a
Hume, or a Leibniz, for the chief element of the philosophy of all
these
men consists in ratiocinatio,
that is to say, the pondering in Reason,
and progress through pure conclusions of Reason. Here, on the contrary,
we see a man whose chief work, unfortunately never finished and only
known
by fragments, was to carry the title of Le Monde, ou Traité de
la
Lumière! So it was the whole great world, the Kosmos as
we
should
call it to-day, and in it first and foremost the medium by which it
becomes
known to us, namely Light, — that it was his aim “to observe, to
investigate,
to grasp,“ and only the man who keeps this aim before his eyes can hope
to gain a correct appreciation of the personality of Descartes, and of
the gifts which it bestowed. If we lay a one-sided stress upon the
intellectual
and theoretical reflections of this man, together with his metaphysical
discussions on mind and matter, and his attempts to set forth
irrefutably
the existence of God and the immortality of the soul, — then we shall
not
only obtain a crooked picture of him, but we shall at the same time not
even be in a position rightly to grasp his peculiar method of looking
upon
these purely speculative questions. The man who does not study
Descartes'
physics and does not penetrate their essence, sees his metaphysics in a
false perspective; that accounts for the inadequateness of all the
representations
of Descartes in philosophical books.
But
the same ill
luck pursues
him elsewhere; for he hardly fares better at the hands of the
mathematicians,
mechanicians, physicists, and anatomists than he does at those of the
philosophers.
Inasmuch as we are living under the domination of the extremest
specialisation, every
single branch of
science only
enquires after concrete services rendered within its own especial
kingdom,
and it is upon these that it reports, whereas Descartes' peculiar
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DESCARTES
domain is the
buffer-state. As between
metaphysics and physics, so in all cases Descartes is happiest on the
frontier.
There where union and separation take place, where the coy facts are
forced
in the interests of combination with other series of facts to become
supple
and accommodating, — there where everything arises which we call
“explaining“
and “understanding“ — there it is that Descartes at last feels himself
at home. For that reason, and for that reason only, he devotes himself
passionately to the study of mathematics, the great mediator between
perception
and thought, between things that are visible and thoughts that are
invisible.
But even mathematics, to the furtherance of which he rendered undying
services,
are to him “only the husk, not the essence“; to work at pure
mathematics
for mathematics' sake he looks upon as aimless waste of time, and he
hurries
so that it is difficult to keep up with him through the technicalities
of form and place, in order that he may come at once to Physics and
mechanics;
but here again it is not the detail of the phenomena which interests
him,
but the Essence of Light, the Causes of Gravitation, the relationship
between
the mechanical laws of Matter and the Facts of Life, and so forth. It
is
true that if he dissects a brain he will give an exact anatomical
description
of it, 11 but what
grips him is the hope of discovering a visible
connection
between the morphological figure and the function of memory. This last
example shows you with special clearness how in this peculiar man
theoretical
thought and the desire for concrete perception went hand in hand. It
followed
that Descartes, in the individual sciences, achieved less than might
have
been expected from a man of his genius. His theorising was detrimental
to the freedom of his observation, while at the same time the freedom
of
his theorising was narrowed by the painstaking detail-work of his
observations.
Hence it is that even his undeniable
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services in the domain of
the exact sciences, — his
informing thoughts as well as the discovery of facts, — reached their
goal
for the most part in other hands, not in his own, and therefore are
assigned
to other names. For example, there is documentary proof, though no
notice
is taken of it, that he taught the gravity of air and made experiments
upon it, when Pascal was a boy and Galilei still maintained the horror
vacui as an unassailable dogma,
— as also that the
famous
experiment
of the Puy de Dôme was only undertaken under pressure from the
unbelieving
Pascal; 12 that
Descartes should have discovered the circulation of the
blood independently of Harvey, and the laws of falling bodies
independently
of Galilei, are matters of which the specialists take no heed; but for
the knowledge of his personality they are of the deepest interest;
that
he was the first to expound the mathematical laws of the refraction of
light, was proved by Humboldt as far back as 1847, but I find no
mention
of the fact in any later work; in medical books you will find cursory
mention
of Descartes amongst the leading names under the words “Eye“ and
“Brain“ — as you see mere fragments, mere insignificance, or — Nothing.
That the
perceptible idea of the inertia of matter lies at the bottom of our
whole
mechanical science, is a matter of common knowledge, but few know that
we are indebted to Descartes for it, and there is not one who prefers
to
base his judgment of the nature of such a mind upon an intellectual
feat
like this and others, rather than upon the cogito, ergo sum. 13 Just as
little is it remembered that it was Descartes who paved the way for a
revolution
in Physics similar to that of Copernicus in astronomy, when he
nourished
the inspired conviction — which to his contemporaries was
incomprehensible
and seemed sheer madness; — Light is motion; and that moreover not the
trajectory
motion of a body violently flung, as Newton taught, but the motion of
an
imponderable
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DESCARTES
matter, the aether, by
which our optic
nerve is made to oscillate. Under the passive domination of the clumsy
Newtonian ideas this thought was forgotten, and when, in order to
justify
the facts, it had to be taken up again, men preferred to attach
themselves
to Christian Huyghens — a son and grandson of
two most intimate
friends of Descartes, — who had grown up under the eyes of the great
man,
and who had further developed his inspired thoughts as to Aether and
Light
into the ultimate mathematically and fully developed theory of
undulation.
And so the constructive thoughts of Descartes are not only the basis of
our atomistic physics, but also of our molecular physics. And in spite
of all it is but little that we learn about him in the books on natural
science, and here too his form remains clouded and distorted before our
eyes.
I hope
that I shall
incur no displeasure
for having shown you so circumstantially how far and why Descartes has
seldom been honoured in accordance with his merits, and why his
personality
is perhaps never rightly judged. I had to introduce this negative
method
of dealing with the question, because I had it at heart to upset what
you
might possibly know about him, or rather that is to say, think you
know,
in order to make way for more correct views. In the meantime I hope
that
you will yet have learnt something, and feel yourselves nearer to the
true
Descartes than you did a while ago. And I set great importance upon
your
knowing exactly what were the views of this remarkable man's brain:
for
in my lectures this brain constitutes the turning-point of our
observations
of Kant's personality, just as he himself, in more than one respect,
constitutes
the turning-point of human thought in general. I purposely use the word
Brain, not System, not Metaphysics, not Discoveries: the system of
Descartes,
that is to say, his Kosmology as it is developed in the Principia and
elsewhere,
is distasteful, that is to
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DESCARTES
say, distasteful if we
examine it with
painstaking accuracy like a dogmatic structure, without paying
attention
to the author's warning to read his systematic works as fast as
possible,
comme une fable or ainsi qu'un roman; 14 his metaphysics, in spite
of
the fact that they are the point from which all later thought proceeds,
are at once jejune and extravagant, without ideas and at the same time hyperphantastic; he
never, with
the single exception of the explanation of the rainbow, 15 followed up
and
worked out his discoveries to the end in a satisfactory manner: at one
moment he allows himself to be choked by empirical detail, in the next
he soars into hypotheses which in the plethora of artificially
interlaced
distinctions of detail are but ill calculated to further the strict
beeline
of investigation. We will not dispute with him about that, but far
rather
learn to recognise with Vauvenargues the fact that Descartes has often
seen right and guessed right, even where he was in too great a hurry to
press forward in the combination of hypothetic causes; ordinary
intellects
have nothing to fear from such mistakes, les esprits subalternes n'ont
point d'erreur en leur privé nom, parce qu'ils sont incapables
d'inventer,
même en se trompant. 16 Descartes himself, in his
wisdom, knew
full
well how that matter stood, and often gave expression to this
appreciation
in the words: “it is enough if I clear the road, you must do the rest“ 17 — and therefore I say
once more of him his work is of less importance
than the Man himself, or, as I said before, the Brain. We men are a
right
foolish folk: here is the one philosopher of all others, in whom first
and foremost personality in the very special character of its
intellect,
and only in the second place systematic doctrine, forms the driving
power
and the lasting interest, and yet it is in this very man that we have
allowed
personality to escape us! Still, in the after life of history certain
men
enjoy an inexpressible immortality: this Descartes possesses
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DESCARTES
almost more than any
other man; for the
thoughts which that brain thought, and even more than the thoughts, the
way and manner in which that brain grasped the chief problems of
existence, — what
therefore we must call the Manner of Seeing, the manner of directing
the
Eyes outwards and inwards, — all this has so penetrated, impregnated,
and
informed our philosophy and our natural science, that all of us, no
matter
to what school we belong, are compelled to weave the warp and woof of
our
thoughts in the loom of Descartes. Rightly did Huxley, one of the few
philosophically
trained investigators of Nature of the nineteenth century, remark: “In
all
thoughts which are characteristically modern, whether in the domain of
philosophy or in that of Natural Science, we find, if not always the
form,
still the spirit of the great Frenchman“; an acknowledgment for which
one
of the best authorities upon Descartes, Count Foucher de Careil, coined
the epigram, On se croit nouveau, on
est Cartésien.
It was
first and
foremost the
whole attitude of the intellect, namely the unconditional enquiring,
which
made epoch. Descartes' intellectual attitude is sceptical,
— but in the old
meaning
of the word.
For the verb skeptomai
originally meant to see, to contemplate, to
investigate,
later to ponder, to reflect upon. In the word sceptic in old days the
stress
was laid upon investigation and careful contemplation (Gellius called
the
sceptics quaesitores et
consideratores). The instinctive wisdom of the
language-forming powers united the perception by the senses with the
necessity
of exact careful investigation, but not with the meaning of doubt which
disintegrates everything, which arose in the decadence of Greek
thought,
and impressed a new meaning upon the word skepsis. The barrenness of
philosophical
scepticism is by its narrowed sense confined to logical functions: it
neither reaches outwards to
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DESCARTES
empirical Nature, nor
does it reach inwards
to confident self-consciousness; the outer Nature as well as the inner
essence should have taught the sceptics that that which is a matter of
fact does not necessarily hold its own before the logical Forum. The
ancient
scepticism arose out of shallow thinking, and led to frivolity, whereas
the scepticism of Descartes, on the contrary, means an awakening of
mankind
out of the sleep of dogma to free, enquiring use of the eyes. Descartes
did not doubt for doubting's sake, but, on the contrary, in order to
help
forward the discovery of a possible knowledge. Non que j'imitasse les
sceptiques,
... au contraire tout mon dessein ne tendait qu'à m'assurer,
et à rejeter la terre mouvante et le sable pour trouver le roc
ou
l'argile.
The old sceptics, however superior they might think themselves,
remained
snared in superstition up to their necks; while Descartes was in all
earnest
endeavouring d'entreprendre
d'ôter une bonne fois toutes les
opinions
que j'avais reçues jusques alors en ma créance.
Now if
Descartes'
doubts had contented themselves with leading us back to that perception
which he used to clothe in the words cogito,
ergo sum, or dubito, ergo
sum, or sum, cogito, sum
cogitans, and the rest, that of itself would
have
been something: Kant
calls him on that
account “a benefactor
of the human Reason“: but, in fact, this result of critical
reflection
simply means the solstice of the Cartesian method of thought: it
constitutes
the point where motion reverses its direction to cross over from the
negative
to the positive. The cogito, ergo sum
is a perception on the
boundary-line,
just as with Kant, das ding an sich
(“the thing in itself“) is a
conception
on the boundary line, and it is only fools who find a pleasure in
running
their heads against boundary stones of this sort. Descartes was no such
fool. On this furthest boundary line, upon the “rock“ of his search,
he
raised a church to the God without whom he could not live; to prove the
existence
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DESCARTES
of God is always a thorny
undertaking,
for He stands beyond the boundary of Descartes: yet this God not very
religiously
felt by Descartes, who had been educated in a Jesuit school, is less
pressed
upon us as something proven than made plausible as a necessary
assumption,
and has the one advantage that he is a God of truth. Descartes needs
Him
only in the interests of truth, in order that what is should be true,
and
for no other purpose. 18
And now the bold investigator addresses himself
to constructive intellectual work! He turns his back upon that boundary
stone, — in his church he only kneels now and again for short worship:
on
the other hand he enriches the world with thoughts which are so full of
life and freshness by reason of their visibility, that they have defied
all the storms of time, and he bestows upon it a wealth of perceptions,
which shelter such an inexhaustible symbolical store of truth, that,
while
reminding us of the oldest traditions of our race, they point to times
that are yet to come.
Pray
do not believe
that I am
using the language of hyperbole: my words are to be taken literally. As
examples I will cite a thought introduced by him into philosophy, and
an
idea introduced into natural science. Descartes' analytical reference
of
the united subjective and objective experience of man to the two
conceptions
extension and thought is an idea so simply
perceptible that it never
can
cease working productively: to this day all philosophers fasten on to
it.
They may use different wool and weave different patterns, still they
are
weaving at Descartes' loom — as I said before — all of them. On the
other
hand,
a conception like that of the imponderable matter filling the whole
universe,
the aether, is so rich in symbolical, thoughtful, creative power, that
it
is only now that, in the light of new discoveries, we are at last
beginning
to recognise its great fruitfulness. 19
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DESCARTES
In his work
on the
immortality
of man Herder remarks:
“It is incredible
how few
special forms
in the realm of thought and human activities appear when we put history
to the test. There are far fewer Regents who govern the world of the
sciences
... than Monarchs who rule over countries.“ There you have, expressed
in a short formula, the merit of Descartes. He is one of those
incredibly
few who produce special forms in the realm of thought — and here, since
an
exposition of the philosophy of Descartes would lead us too far, we
must
give up the enumeration of the special forms which he introduced: but
what
we must keep our keenest sight upon is the way in which this man,
receptively
and creatively, looked out upon the world, the way in which he came
upon “the special forms in the realm of thought.“ Let us now apply
ourselves
to this task.
I just
now praised
the great perceptibility
in Descartes' thoughts; at the same time I cited as an example his
theory
of the aether, an imaginary thing, which when we consider it more
nearly
defies all perceptibility. An exact analysis will convince us that, as
a matter of fact, there are two ways of showing this expression of
intellectual
satisfaction which in ordinary life we describe as perceptible
clearness; we are partly dealing with what is seen, partly with what is
thought.
The creative power of the informing faculty of sight, directed upon the
surrounding universe, was in Descartes of such rare might, that a
matter-of-fact
contemporary, the great mathematician Christian Huyghens, on receiving
the news of his death, exclaimed:
Nature!
prends le
deuil, viens plaindre
la première
Le
grand Descartes, et montre ton
désespoir;
Quand
il perdit le jour, tu perdis
la lumière,
Ce n'est qu'à ce flambeau que nous
l'avons pu
voir. 20
As verses these are not
worth much: but
coming from the pen of a Huyghens, they have more significance
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DESCARTES
inasmuch as this
investigator belonged
to the exactest of the exact. And as you hear, he maintains that the
sunlit
world was dark and unseen until Descartes lighted a torch over it, the
torch of thought. We men see nature all blurred, until clear
comprehensions
have reduced the chaos of perceptions to order. Our eye sees but dimly,
until the thinking brain has fixed it sharply, like an optician's
glass,
upon the objects in view. In another stanza of the same poem Huyghens
makes
use of a trope which by the direct opposite completes what he has just
said; for he says of Descartes that he
Faisait
voir aux esprits
ce qui se cache
aux yeux.
This implies that
Descartes gave visibility
to those things which our physical eyes indeed do not see, but which
our
understanding is compelled to think. And so as in the one case he
bestowed
thought upon things, so in the other he conferred upon thoughts the
representations
of the senses: in other words he gave them substance. In the one case
it
was the turning into thought that which had been indistinctly seen, in
the other the turning into something visually perceived an idea which
had
been indistinctly thought.
We
will at once
illustrate these
two sayings of Huyghens by examples. Descartes comes to the help of
perception
when he e.g. explains all the movements of bodies in heaven and on
earth
by the setting up of certain fundamental conceptions such as inertia,
mass,
and others; even these simplest phenomena we never knew how to observe
aright and see aright before the discovery of such ruling conceptions.
To such as these belongs his theory that the Sum of Motion in the
universe
is once for all immutable, a favourite assertion of Descartes which,
for
the first time, brings into the chaotic oscillation backwards and
forwards
and circuitously in the Kosmos, a thought reducing it to order, — a
thought
which, merely
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DESCARTES
amplified by an
additional sentence,
is the foundation of the modern doctrine of the maintenance of energy,
which is at the bottom of our whole science of physics. 21 That will
suffice
for one of Huyghens' affirmations: now for the other. Descartes comes
to
the assistance of thought through perceptibility, when for example he
starts
the theory of the above-named aether. This thought-picture leads us on
to look upon Light as the movement of an endlessly refined,
imponderable,
imperceptible matter, which fills the whole world, a movement which the
optic nerve betrays to us, without showing it, since, of course, aether
is not a thing perceptible and therefore real, but a symbol for
something
which is presupposed in thought, and undefinable. 22 Another example
would
be Descartes' doctrine that it is not the Eye but the Brain that sees;
all impressions of the senses are in the last instance invisible
motions
of imperceptible infinitesimal particles inside the Brain. 23 Here, in
the
case of the hypothetical aether, and in the hypothetical molecular
motions
of the substance of the brain, the visibility which has been acquired
in
what are matters of mere thought serves to a consequential observation
and concatenation of phenomena; true exact science of nature and of
mankind
first became possible by means of this and similar symbols.
Here
you have
obviously two different
intellectual gifts with which our philosopher is accredited, gifts
which
do not necessarily belong to one another, and both of which, if we see
them as purely and absolutely developed as they are here, at once
fascinate
us as something not easy of comprehension. Descartes knew how to give
intelligible
form to that which he saw, and at the same time possessed the power of
transforming that which was only thought into something visible: that
is
the fact to which Huyghens calls our attention. And here in very deed
he
goes straight to the core of the matter,
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DESCARTES
and for that reason his
remark must serve
us as a clue to the further analysis of this unique intellect.
In
order swiftly
and surely to
plumb the depths, I should wish to take the judgment of Huyghens which
I have already traced back to its simplest meaning and reduce it to a
still
more striking, concise, and purposely paradoxical formula. For it is
not
formula but phrases which are a hindrance to vivid insight, whereas a
true
formula serves as a skeleton round which the organs of the living
figure
by degrees arrange themselves. My formula runs thus: — Descartes'
distinguishing
gift was to make the visible invisible, and the invisible visible.
If you
look around
you in the
world of your own contemplative consciousness, you will soon observe
that
the degree of perceptibility of the ideas which fill it is exceedingly
various, and the same holds good of the possibility of conceiving them.
And you will soon be aware that there exists here a very complicated
interchange
of displacements, a mutual give and take. We possess thoughts with
hardly
a shadow of a perception, and we possess perceptions which are attended
only by just such a minimum of thought as is necessary for us to be
conscious
of those perceptions. Our daily life is made up in that way. Without
venturing
further I will only call your attention to one thing, and that is that
a thought that is accompanied by a blurred, hardly realisable
perception,
therefore an “invisible“ thought, can achieve but little, and that on
the contrary pure perception soon grows into something monstrous,
intractable,
inflexible, unless thought takes the pains to seize upon it and convert
it into something unseen. We are in no way embarrassed to find concrete
examples, we need only think of our two first lectures: It was by a
thought
and in the interests of a thought that Goethe brought together the
whole
incalculable mass of animal and vegetable forms into his idea of
metamorphosis: and so he breathed
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DESCARTES
the artist's soul into
what was a mere
brutal observation, furthering the investigation of Nature for all
time;
Helmholtz, the physicist, rightly taught us that the powers with which
mathematical science deals cannot be “objects of the perception of the
senses,“ but only “objects of the comprehending understanding“; yet
Helmholtz,
in his work on optics, has none the less to take refuge in plain
diagrams,
first the wet thread, then the ray, which like the sailor swarming up a
rope, “produces itself along the particles of aether,“ and so he goes
on
from diagram to diagram because this thought of the “comprehending
understanding“
could not be realised and appreciated without a perceptible
representation.
This is the way in which we human beings, half unconsciously, are for
ever
changing the visible into the invisible — in order to see it better, —
and
the invisible into the visible, — in order to think it better. Kant,
from
his metaphysical eminence, has summed up what I am here only concerned
to show in a concrete and visible shape into the following pithy
sentence:
“thoughts without contents are empty; perceptions without
comprehensions
are blind. Hence it is just as necessary to make our comprehensions
perceptible
to the senses, as it is to make our perception intelligible, that is to
say, to bring it into subjection to comprehensions.“ Kant is here
speaking
of the common, unconsciously proceeding, necessary functions of all
human
reason from the moment that it enters into activity in the new-born
babe:
allow this reason to ripen to such an extent that it desires to build
up
for itself a science and a philosophy, and you will find this reason
standing
as conscious intelligence exactly where at its first awakening it stood
unconscious. Then it begins to take matters easily; it seems so natural
not to follow Kant's warning, but to be busy with empty thoughts and
blind
perceptions, that three-fourths of all philosophy from the earliest
times
to the present day
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DESCARTES
has never busied itself
with other things.
The writings of St. Thomas Aquinas, for instance, are an inexhaustible
arsenal of ideas, which are incapable of exciting the smallest
thought — mere
“blind perceptions“; and if you skip from the thirteenth to the
nineteenth
century, you will find that the most popular of all the more modern
systems,
that of Schopenhauer, takes as its foundation-stone a thought which is,
according to Kant, utterly empty, the one which it calls Will and
which,
according to its definition, is the opposite of an idea and
consequently
contains nothing capable of being in any way perceptibly understood.
All
such thought-structures are extravagance, not knowledge: Kant once
formulated
this very simply. “By mere perception without comprehension the object
is certainly given, but not thought; by comprehension without
corresponding
perception it is thought, but none is given: in neither case,
therefore,
does any recognition take place.“ How, on the other hand, perception
and
thought, the visible and invisible, go hand in hand towards the
building
up of systems of philosophy which explain nature, you may best see from
the histories of our natural sciences, the development of which was
conditioned
by this mutual penetration. Let us here pause for reflection.
Think
of how, at
the beginning
of the seventeenth century, Copernicus and Kepler are unravelling in
its
main features the course of the planets round the sun; from the leaning
tower of Pisa Galilei makes minute observations of the fall of
bodies, — instead
of merely reasoning logically upon it as all his predecessors had
done, — and
pursues his studies upon inclined planes; Descartes and others with
keen
intellect and patience follow up the mysterious course of the
Light-ray,
its curves, its refraction, its reflection; Gilbert publishes his
observations
on magnetism
... from all sides
there comes in
a stream of additional matter, — that is to say, material of
observation,
and in
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DESCARTES
every single sphere the
empirical investigators
are at work trying to the best of their ability, as Kant demands, to
make
their perceptions intelligible, that is to subject them to
comprehension.
Yet here we discover something over which we need not for the moment
break
our heads, but which we will simply accept as experience; namely that
thought
cannot directly fasten upon the perception of the senses, but must
first
with that intent create its own mental perception, — that which we call
Symbol
when we are wishing rather to bring to the front the perceptible side,
Hypothesis when we are dealing with the mental side. Thought must
create
unity: this is its special function: pure perception only gives a
kaleidoscope
of special cases. Therefore perceptible thought cannot proceed without
Symbol; it cannot, without further help, grasp, comprehend, and absorb
the material of perception: without Symbol it remains empty. I can have
no thoughts about the courses of the constellations, about the fall of
bodies, or about the essence of Light, unless I also possess, besides
the
empirical material, and for its amplification, a symbolical
representation
of what takes place in that connection, — in other words something
intermediate
between perception and thought. And here my intellect makes a further
claim.
Not only must phenomena, within the individual series of phenomena be
joined
together by means of symbols, but all the separate series of phenomena
with which I have become acquainted by means of empirical perception,
must
in addition be capable of being understood as one single comprehensive
unity. For as Kant will teach you later on, that which we call Nature
is
“the unity of the multitude of phenomena,“ as it is set forth as a
matter
of subjective necessity by our thoughts. It is impossible for me to
realise
a number of natures. The grouping of the planets round the sun, the
grouping
of the steel filings round the pole of a magnet on my desk must be
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taken as energies inside
one symmetrical
Whole. And here the great Descartes steps in as a creative power: he
produces
a new “special form in the sphere of thought,“ he changes into
visibility
that invisible something which our understanding insists upon though it
cannot perceive it, — he fills thought with contents: this he is able
to
do in that he sets up the perceptible hypothesis of a medium filling
space,
of a matter absolutely refined, invisible, imponderable, fluidly
moving — the aether, a symbol, the child of his phantasy. 24 At once all the
phenomena
mentioned enter the domain of demonstrability and so become accessible
to the constructive labours of thought: the aether carries and urges
the
stars in their courses, the aether as a driving mass becomes the
foundation
of the phenomena of gravitation, one set of movements of the aether
gives
birth to what we call the warming of bodies, another set to light,
others
to electricity and magnetism, and so forth. I refer you to my former
lecture
and am confident that this one example will show you with extraordinary
clearness what is meant by “making visible the invisible.“ At the same
time you will learn how indispensable perception is to thought, even to
the possibility of thought. Descartes had indeed by his hypothesis
poured
out such a wealth of visibility over the secrets of Nature, while he
Faisait voir aux
esprits
ce qui se cache
aux yeux‚
that the eyes of
men were
dazzled by
it. In those days neither the collected empirical material was
sufficient,
nor was thought adequately trained and refined to be fit for so grandly
simple a symbol for all the physical phenomena of movement of the
Kosmos.
Besides this Descartes in the closer elaboration of the matter had
fallen
into an error for which he was reproved by Goethe; “he attacks the
insoluble
problems with a certain hurry, and for the most part enters the subject
from the side of
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DESCARTES
the most complicated
phenomena.“ 25
There
is much that is artificial and arbitrary in the use which he makes of
the conception of the aether. The startling simplicity
of the general
conception
is marred
by all sorts of hazardous amplifications in detail. But it is just
here,
as is the case with every important man, that we learn how far
greatness
and limitation are set side by side, conditional and conditioned. And
so
it soon came about that Newton with his keen intellect, at once exact
and
barren of all imagination, once more seized upon the scholastic
fictions
of forces working at a distance, and took the old conception of Light
as
a special Matter: Newton's ideas are in the same relation to Descartes'
ideas, as those of a child to those of a man; and yet they corresponded
exactly to the requirements of empirical investigation in those days.
At
the present time, when new matter has been accumulated by the work of
centuries,
we are gradually going back to Descartes and his symbolical method of
thought:
in the case of the understanding of Light this took place about a
hundred
years ago with the introduction of the undulation theory mentioned in
the
last lecture; in the case of the electric magnetic phenomena about half
a century ago; physical experiments to explain gravitation as
conditioned
by the movement of aether, exactly as Descartes postulated, are the
order
of the day, 26 and
the great Hertz, so early torn from the world, was
possessed
in death by the dream of reducing “the putative working of the distant
forces to conditions of motion in a medium filling space.“ 27 Lord
Kelvin — and
following him many modern physicists, go still further and contend that
the various atoms which chemistry admits are only different gyratory
motions
of the one and only aether: that there must therefore be no such thing
as Matter, but Aether only: in this most exact method of investigation
the “Thing“ fades away, the Symbol alone remains. In a symbol so
solidly
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DESCARTES
perspicuous is contained
the principle
of robust vital power.
So
much for the
explanation of
the transformation of the invisible into the visible. “Perceptions
without
conceptions are blind,“ says Kant. Even as I could not budge an inch in
the realm of thought unless I possessed a “reasoned“ perception, so I
must remain helplessly stuck in the quagmire of perception, unless I
should
have thoughts to drag me, as horses drag the cart, out of my
difficulties.
So be it. But how am I to obtain conceptions for my perceptions? Here
again
an intermediary something is necessary. Perception cannot directly
become
conception; the intermediary image is the Scheme. We men are incapable
of taking into our inner consciousness anything seen or in any way
perceived
by the senses, unless we have previously in our thoughts reduced it to
a Scheme. This is an aptitude which differs greatly in different
individuals; yet if a man were altogether unable to generalise, that is
to reduce
the many perceptions to few schemes, it would certainly be impossible
for
him to think; for, as Kant hits the point by saying, his perceptions
would
be blind; he would see, but not recognise. In the last lecture we saw
how
the great painters schematise: a purely perceptible scheme is still
sufficient
for their object; only a minimum of conception enters into it. In a
somewhat
different fashion, but in obedience to precisely the same universal law
of human reason, science goes to work. Whereas the painter wishes to
see
yet more clearly that which is already seen, and calls to his aid
conceptions
for that sole purpose, the investigator of nature wishes to conceive
more
clearly that which is seen, and to transform it into something known.
When
in this process of perceptible reasoning it is that which is
perceptible
which is preponderant, we speak of a Scheme; when, on the other hand,
it
is the element of thought which preponderates, we
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speak of a Theory. Theory
and scheme
belong to one another as Hypothesis and Symbol. Now we know exactly
with
what we have to deal; in order to obtain a concrete example, we must
return
once more to the seventeenth century.
This
time we must
work within
narrower limits; we will only take into consideration the works upon
the
visible movements of perceptible Bodies: for we shall busy ourselves
not
with hypotheses but with seen facts. Let us then confine our thoughts
to
the way in which some men in those days busied themselves with the
observation
of the movements of the heavenly bodies, and how others, — the immortal
Galilei
in the forefront, instituted eager experiments on the movements of
bodies
on our earth, that is to say, on the fall, the impetus, the rolling off
upon inclined planes, upon the trajectory of projectiles, upon the
communication
of motion from one body to another, and many other similar matters. The
physical acceptations of the ancients proved themselves to be utterly
false: new, accurately observed facts accumulated. How to order them?
How to
“make the perceptions intelligible“ ? How make what took place on earth
consistent with what took place in Heaven? the fall of the apple from
the tree with the circuit of the moon round the earth? Exactly as man
had
before, by submitting to thought the perceptible idea of the aether,
come
to the assistance of thought, so he had to act now in order to make his
perceptions visible and capable of being surveyed: he had to remove the
cataract from his eye, and that could only be by means of
comprehensions,
by referring all the single conditions of motion to a scheme which
should
be in accordance with rule, artificially thought out, and capable of
being
grasped logically; not given to him by the empirical observation of
Nature,
but set up autocratically between the eye and Nature by the King in
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his Castle of whom I
spoke in the first
lecture. Here again it was Descartes who laid down the principles of
our
modern theory of motion, and at the same time of our whole science of
mechanics.
All
movements of
visible bodies
may, as a matter of common knowledge, be referred to three fundamental
laws, which we usually call after Newton, because he was the first to
crystallise
them in words, and has developed them in all their sequence. 28 But the
third of these, which is not to be found in Descartes, is by universal
consent recognised as a formal amplification of the first, 29 and even
so
very disputable. 30
We have to deal therefore with two, not three,
fundamental
laws, and these two laws were not thought out by Newton but by
Descartes;
Newton took them over almost literally from Descartes, though the
latter
had not worked them up to such perfect refinement. 31 All that the
so-called
“first Law“ of Newton contains — that Rest and Motion are not
opposites,
but only conditions of a body, — that every body left to itself remains
perpetually
in its own condition whether of Rest or of Motion, — that the body
which
is set in motion, unless there be some hindrance, will continue to move
in a straight line with unaltered speed for all time, — all this stands
word
for word in Descartes. And I must call your attention to this, that no
single one of the thoughts uttered in this law is the result of
observation,
or even capable of proof by experiment. 32 The second law of Newton
too,
which treats of the mensuration and direction of the Motion which is
communicated
by one body to another, is contained without a single omission in
Descartes.
It is he then, and no other, who perfected this creative work of
thought.
But here again, as in the case of the aether, Descartes overshot the
mark,
and like Dürer in his doctrine of proportion, introduced
superfluous,
and even in the end false, matter, so that the sure tact of a Newton
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was sadly needed to
purify the core from
the slag. But the only thing that is of interest to us here, is the
fact
that Descartes, by the introduction of a few schematically theoretical
conceptions, contrived to unravel and so make available for mental
elaboration
that which winds itself round our senses from childhood, — that in
connection
with which the whole united antiquity never achieved clear ideas, —
that
which the great calculators and experimenters of the fifteenth and
sixteenth
centuries failed to set free from the entanglements of the whole
material
of perception; I mean the Phenomena of visible motion. Here again as
you
see is a “new form in the realm of thought.“ And here as in the former
case the value of such a creation for science and philosophy is
immeasurable.
For just as the symbolical hypothesis of aether paved the roads for
thought
upon which it was now possible to arrive at a rational appreciation of
the phenomena of light, of electricity, etc., by means of a visible
representation,
so in this case the setting up of a schematic theory of Motion based
upon
metaphysical conceptions allows us to range the over-rich mass of facts
seen into a few schemes of thought, where they can be guarded inclosed
in formulae. For there is the turning-point: since the Visible is as
fully
as possible, — in some lucky cases altogether, — transferred into the
realm
of the Unseen, of that which is as yet only thought, it possesses a
handiness,
a pliability, a movability, which otherwise are foreign to its own
perceptions, — purely
as such — and are dull, inert, awkward: they are, just as Kant taught
us,
blind,
and grope about in the dark; but as soon as the human understanding has
arranged them into comprehensible Schemes then it does with them as
seems
good to it, dissects a Whole into Parts, unites Parts at will, in short
behaves as it chooses: it is Lord in its Castle.
We
have now, as I
believe, made
an important advance in the understanding of the universal relations
between
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DESCARTES
thinking and
seeing, — which collaborate
in so peculiar and twofold a combination for the building up of a
system
of philosophy, — as well as in respect of the recognition of Descartes'
special
aptitude for acting as intermediary between them. Our formula that
Descartes'
distinguishing gift was to make the visible invisible and the invisible
visible, is no longer a formula, but an Insight. But I cannot let the
matter
rest there. Kant's thinking is a pinnacle of the human intellect; no
man
can reach him who shirks the trouble of climbing. It is therefore
indispensably
necessary that you should yourselves now enter upon the region which
lies
between perceptive seeing (or the sensitive faculty) and the
understanding,
which binds together comprehensions:
otherwise you will
only
be possessed
of partial, not complete, distinctness.
Let
me, however, in
a parenthesis
introduce a short remark upon the subject of Symbol, Scheme,
Hypothesis,
and Theory. It is not a question of mere terminological clearness, but
of a visible representation, which will also be useful to you
philosophically.
The
Symbol, in
fullest acceptation
of the word, is the perceptive demonstration of that which is thought:
the Scheme, in its widest sense, is the rendering into thought of that
which has been perceived: the Symbol furnishes thought with a thinkable
perception; the Scheme furnishes perception with a visible thought.
Within
the symbol, however, it is possible to distinguish between a more
purely
perceptible and a more mental conception of the demonstration: the
result
of the first is the true Symbol, that of the second is the Hypothesis.
In the same way the Scheme splits up into true Scheme and Theory. From
this I draw the following explanatory diagram.
The
advantage of
this diagram
is that it accurately describes the mutual relationships of these
different
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DESCARTES
conceptions — that is to
say, if I may
so express myself, their mutual position in the Space of Thought. You
see
at a glance that if, on the one hand, Symbol and Hypothesis are
related,
on the other the relationship is between Scheme and Theory, while
Hypothesis
and Theory, Symbol and Scheme in the same way lie close to one another.
A very slight mental impulse suffices to turn a Symbol into a
Hypothesis,
and a Theory into a Scheme; it is a sort of swinging of the pendulum
that
our intellect
is carrying on the
livelong day without
paying attention to it. But even the boundary between Symbol and
Scheme,
as between Hypothesis and Theory, is not insuperable: a small change in
the standpoint suffices to give a colour of Scheme to Symbol, and a
colour
of Symbol to Scheme, and in the sciences Hypotheses have a way of quite
quietly, according to seniority, slipping into Theories. On the other
hand,
as regards the two pairs which stand crosswise to one another, Symbol
and
Theory, Hypothesis and Scheme, it is a matter of impossi-
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bility for them to be
changed into one
another. But what cannot occur directly may sometimes be effected
indirectly,
and so it often happens in the Natural Sciences that a Hypothesis by
degrees
acquires the value of a Symbol, becomes schematised, and at last stands
in all the dignity of a Theory. In the course of time that which is
really
only thought, and as such in a slight degree hypothesised, has managed
to assume the character of perceptibility to such a degree, that it is
conceived as practical perception, and is then converted into thought,
so that it takes the shape of a Scheme, and in the end of a full-grown
Theory. With the aether, for example, it is always the case, until
often
some new discovery suddenly reminds us that this idea only possesses a
symbolically hypothetical value; that is the way in which we men
befool
ourselves without any suspicion that we are doing so. The inverted
process
from Theory over Scheme, and Symbol over Hypothesis, which hardly
occurs
in science, is, on that account, common in everyday life. That which is
seen is converted into thought by Science, but the layman comprehends
scientific
schematic thought as true perception: indeed, we have heard a Helmholtz
talking of particles of aether “along which“ a Ray moves!
This,
however, is
only a side
issue. You must draw from it the one distinction between thinking and
perceiving
which is perpetually being forced to and fro in our brains. Perhaps in
addition to that the small artificial Scheme may render us good
service.
And
now let us go
back to Descartes.
From
the two
examples that we
have taken, aether and the laws of motion, you will perhaps already
have
begun to suspect that thought and perception are not merely
transiently,
but really and permanently divided from one another. A complete fusion
between them never takes place. There is never so much as an attempt at
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such a fusion. The world,
as we perceive
it by our senses, does not satisfy thought, and never has satisfied it:
for the world is incapable of thought, only our brain is that:
and so thought
creates
for itself a
Kosmos of its own, a special perception “converted into thought,“ and
discovers
at one time the Atoms, at another the Aether which the modern
science
of physics designates simply as “unperceivable matter and invisible
motion.“ 33
And yet thought does perceive the unperceivable because it wills to do
so; and thought sees the invisible because in no other way could it
build
a bridge by which to attain perception, or make a road by which to
reach
the dreams and works of Reason. We may grant that this aether, this
atom,
is something perceptible, indeed it is seen with all the special
intensity
of a dream-picture, and it is only thanks to this vision that thought
can
climb aloft. In spite of this the aether, like the Atom, is sicklied
o'er
with the pale cast of thought, and — again like a dream-picture, as we
advance
they retire and ever elude our grasp:
they are indeed
not
perceptions of the
senses, but perception that is thought:
a symbol is not a thing: the
man
who seeks to investigate aether and atom by perception, is tilting
against
something that does not exist. The analogy holds good with our
perception.
The schemes upon which we base our experiences in the matter of the
movement
of bodies have for their aim the transferring of these perceptions into
the domain of the comprehensible: here it is, and nowhere else, that
thought
like a mighty tree must carry and nourish the monstrous rootless liane
of empiricism that is “conscious of no bounds.“ In this case our aim
is
to convert what we have seen into a quantity, that is to say into
something
so far only thought; colour becomes a quantity of oscillation, and a
man
born blind can talk as much wisdom about it as a Titian.
But
should you not
yet be convinced
that it is the
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intimate laws of the
human intellect,
the fundamental facts of metaphysics, that are the informing power that
is at work here, — should you imagine that without calling to your help
metaphysical
discussions you can arrive at clear notions about Time and Space, and
about
Motion in space and time, I will instead of laying before you arguments
for which you are not yet prepared, address one request to you: I would
ask you to refer to the scholion on the eighth definition in Newton's
mathematical
principles of natural science. It is the man of distinctly
anti-metaphysical
principles who is talking to you, and that indeed in a work of
imperishable
importance. In the beginning of the passage in question he declares
with
disconcerting guilelessness — “Time, Space, Place, and Motion, as
matters
of common knowledge, I do not explain.“ 34 If the question were
merely
one
of dealing with the simple perception of these things, then an
explanation
of time and space would be as little necessary for the greatest
intellect
as for the most narrow-minded cow-herd. It seems to me that this
postulate
was altogether insensate: that which is self-evident cannot gain in
value
by explanation: on the contrary, it is out of the life that the word
comes.
Descartes' warning is: il faut
mettre au nombre des principales
erreurs
qui peuvent être commises dans les sciences l'opinion de ceux qui
veulent définir ce qu'on ne peut que concevoir. But there
is no
question of time and space, as they are known to all, — Newton himself
will
presently teach you that this would not lead us one step further in
Science, — but
with that intent it is our business to transfer that which is seen into
that which is thought, and vice versa, and so we arrive at inextricable
confusion until a critique of human Reason has illuminated us. Read a
little
further in Newton's scholion. You will find there things about
“absolute
space“ (spatium absolutum)
which are not less edifying than the
properties
of the absolutum quid of
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DESCARTES
the schoolmen. This “absolute
space is
without relation to any outward object“ (sine relatione ad externum
quodvis);
but there would be little to be made of a thing which stands in no
relation
to anything; therefore, in addition to this absolute space, relative
spaces
are assumed (in quantity), and these relative spaces are movable in
absolute
space of which they constitute the parts! I do not think that the human
intellect has ever attempted to imagine anything so monstrous as this
quantity
of spaces, which move about in confusion. It is true that these
movements
are only a passing idea such as might appeal to the intellect of our
aforesaid
cow-herd, for immediately afterwards Newton gives utterance to this
deep
reflection: “if the parts of space are turned out of their place they
are, so to speak, removed from themselves“; but even that will not do,
and so we receive the amplifying assertion about these relative spaces
—
“the spaces are their own places“ (spatia
sunt sui ipsorum loca). And
when
you are stuck fast in this utterly senseless empirical jumble, you are
taught that this space (of which you were told on the previous page
that
it is such a matter of common knowledge that it needs no
explanation), — is
beyond your ken, and that “you are not able to separate its parts by
means
of your senses“; and therefore, and here comes the gem of the whole,
since you are dealing with something not perceptible to the senses,
something
impossible of distinction, therefore, quoniam,
you must assume
perceptible
mensurations (mensuras sensibiles).
So with perception you are to reach
the invisible, and to measure something the parts of which you are not
able to distinguish! The cause of this confusion which could only be
cleared
up by the highest critical circumspection and the finest analysis, lies
in this, that mankind is not possessed of a clear appreciation of its
own
intellect: we interchange the Scheme which is only capable of being
thought
with the
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true perception of the
senses. There
in the case of aether (just think of the theory of undulation and its
powerlessness
in respect of colour) that which pertains to thought intruded into
perception
with disastrous results; or perhaps it would be more correct to
say, — since
the aether is, as you will remember, a thought converted into
perception — the
human intellect proved incapable of producing out of its own powers a
symbol
which should equal Nature: here, in the fundamental conceptions of
dynamics
as developed by Newton, the same intellect proves incapable of freely
discovering
thoughts in all portions, that is to say, of converting into thoughts
its
perceptions by the senses. In order to bring our perceptions under a
few
fundamental conceptions we invented the law of inertia: but the
thoughts
of absolute space, endless time, the uniformity of a body, which
according
to definition should be alone, and so removed from all comparison, —
all
this is not known to us by perception. From empirical perception we
borrow
that minimum of perceptions of the senses without which our theoretical
thoughts would be empty, that minimum without which the scheme could
not
be fashioned: but true perception never exactly tallies with this
theoretical
schematisation. And so we come to a standstill as soon as we in all too
great simplicity attempt to satisfy the human intellect without a
metaphysical
critique, although in practice all goes well enough, and a Newton
erects
a building worthy of everlasting admiration when once we grant him a
certain
series of premisses as unthinkable as they are imperceptible. 35
You
see from these
considerations
how important it is accurately to investigate the critical domain
between
perception and thought, and also how many difficulties throw us into
confusion
by piling themselves up against our understanding. Happily there is one
function of our intellect, one, only one, mathematics, which allows us
to
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DESCARTES
clear up this matter to
perfect distinctness.
One general explanation, and then I propose to start upon a discussion
of Descartes' relationship to mathematics: in this way we shall by
degrees
reach daylight, and we shall have no difficulty in seeing how all this
may be applied to the study of Kant.
I
propose here to
insert a diagram
which will serve as a pause, and give my words a really comprehensible
meaning. If we express the range of the human intellect by a
quadrangle, — a
circle would be better, and a globe of course still better — we can in
general
terms affirm that one half belongs to the senses, that is to say, to
perception,
to that which is perceived, the other to the understanding, thought,
the
formation of comprehensions; those are the “two quite heterogeneous
portions“
of which Kant spoke a while ago. A more minute consideration, however,
such as that which the history of our natural sciences has forced upon
us, will soon convince us that pure perception and pure thought are not
directly in contact, but that there is an intermediate domain which
serves
to help the crossing over of the one to the other. There are certainly
no fixed boundaries; we are not dealing with a machine the wheels of
which
simply lay hold upon one another, but with a living structure in which
every single organ in combination with all the other organs forms a
unity
at once real and ideal. Whereas in a watch the parts come first, and it
is only in the end that the watch as a whole comes into existence by
the
combination of the parts, — in a living body the Being itself is the
first,
and that which we are pleased to distinguish as parts or organs, is
formed
by degrees and has never more than a conditional importance in regard
to
the Being, since the division of the functions does not take place, as
in the watch, according to an immutable stencilled pattern, but one
organ
can even take up the duties of another. Still a Scheme will serve our
present
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purpose, and a Scheme is
only clear when
it is schematic, that is to say, absolutely quadrangular and
rectilinear.
So we will draw our quadrangle and assign one half to the Senses (the
Sinnlichkeit
of Kant) and with them to Perception, — the other half to the
Understanding
(as Kant calls it) with its conceptive Thought. But, towards the
middle,
pure conceptive thought crosses over to perceptible thought, and in the
same way, towards the middle, pure perception of the senses crosses
over
into thoughtfulness. This boundary land I will denote by hatchings.
You
have already
seen how the
understanding strove to annex into its own domain the visually seen
perceptions
in regard to Motion, and how with this intent it drew them over, not
without
violence, by the help of Schemes to its own special boundary land of
perceptible
thought; and before that you had seen how the senses had succeeded in
awakening
to a glorious life scientific thoughts which had up to then remained
unfruitful,
and when well considered generally unthinkable, by the means of the
discovery
of a sensible and perfectly perceptible Symbol, the aether.
The
slightest
reflection will
surely suffice to show you what a travelling backwards and forwards
goes
on within the human intellect. If, for instance, in our laws of Motion
stress should be laid only upon the theoretical and arithmetical, which
was the case with Newton the juggler in figures, then these laws end by
losing all perceptibility, they leave our middle line for the boundary
of the hatched part, they become altogether thoughts: but with
Descartes
in these very same laws of motion it was the conception of the senses
which
prevailed, and more recently with Hertz in the same way the
geometrically
perceptible: by those means the thought shifts towards the middle line,
that is to say, towards the Symbol, and Theory becomes relatively more
schematic
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than theoretic. The same
thing takes
place with our thoughtful perceptions. They may belong so entirely to
the
senses, that is to say, they may stand so entirely on the edge of this
hatched region, so far therefore from the half assigned to the
understanding,
that comprehension is not in a position to grasp them. Goethe's
metamorphosis
is an example of that. Descartes' aether, on the contrary, belongs in
an
important degree more to the realm of thought, in spite of being still
quite concrete. The symbol of the aether can be drawn into itself from
the conceptive portion of
our being with
such violence that, as you have seen, in the end every concrete
conception
fades away, and aether subtilises itself into a motion as yet only
imagined,
dispensing with every perceptible, material foundation (see page 130).
In this case then not only is the middle line crossed, and the Symbol
turned
into Scheme, but this Scheme itself is as yet little more than Thought.
I commend to your understanding the Physics of Lord Armstrong and the
“Primitive
animal“ (Urtier) of Goethe as
the two most remote and most opposite
ends
of our “buffer state.“ In the one case a conception (the movement of
the
No-Thing in
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empty space) which wipes
out all conceptibility
down to the uttermost remnant, so that it is impossible to think of it
any more; in the other case a thought (the original creator of all
individuals,
itself without any individuality) has so completely materialised itself
that there remains not even that minimum of conceptibility without
which
no form can be clearly recognised.
From
this
schematisation and this
warning against the misuse of the Scheme, let us now turn to
Mathematics.
The
characteristic
of the science
of Mathematics is that it takes possession of the “buffer state,“ the
hatched part of my diagram, and exactly fills it. Here is a case where
no scheme can be too uncompromising. Both the two forms of Mathematics
(on the one side the perceptible form of the science, — Geometry or the
doctrine
of Forms,
— on the other,
the
comprehensible form, — Arithmetic
or the doctrine of numbers) reach inwardly with exact precision towards
the middle line, that is to say, towards the boundary line between the
two domains of the understanding and Perception by the Senses. But
inasmuch
as mathematical science reaches outwards only exactly so far as the
boundaries
of this intermediate region, and does not cross it, so there arises
between
its two parts a reciprocal independence, an exact Parallelism which is
nowhere else to be found between perception and thought. That which is
thought mathematically contains nothing which might not also be
perceived,
and that which is perceived mathematically embraces no forms which
might
not also be grasped by thought. Here that unconscious shifting to and
fro,
of which we spoke just now, does not take place: every mathematical
conception,
every mathematical representation of ideas, has its appointed and
immovable
place. The two mathematical fields of intellectual operation are not
identical, — the
diagram shows how entirely autonomous they are, — and yet they are a
matched
pair, the one
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being the counterpart of
the other.
On the other hand, the sharp definition of the middle
