articles of faith to our " natural interest " in morality, philo-
sophy admits its powerlessness to advance beyond the ordinary
understanding, Kant propounds one of his abiding convictions,
namely, that in matters which concern all men without dis-
tinction nature is not guilty of any partial distribution of
her gifts, and that in regard to the essential ends of human
nature the highest philosophy cannot advance beyond what is
1 Cf. above, pp. 10, 543. Cf. Fortschritte ; Werke (Hartenstein), viii. p. 561.
2 Cf. Logic, loc. cit. Cf. Foundations of the Metaphysics of Morals, W. iv.
pp. 416-17 : Abbott's trans, pp. 33-34.
8 Regarding Kant's distinction in A 827 = 6 855 between Ideas and hypotheses
cf. above, p. 543 ff. Cf. also Critique of Judgment, W. v. pp. 392 ff., 461 ff. ;
Bernard's trans, pp. 302 ff., 395 ff. 4 A 829 = 6 857.
57 8 APPENDIX A
revealed to the common understanding. 1 The reverence which
Kant ever cherished for the memory of his parents, and for
the religion which was so natural to them, must have pre-
disposed him to a recognition of the widespread sources of
the spiritual life. But Kant has himself placed on record
his sense of the great debt which in this connection he also
owed to the teaching of Rousseau.
" I am by disposition an enquirer. I feel the consuming thirst
for knowledge, the eager unrest to advance ever further, and the
delights of discovery. There was a time when I believed that this
is what confers real dignity upon human life, and I despised the
common people who know nothing. Rousseau has set me right.
This imagined advantage vanishes. I learn to honor men, and
should regard myself as of much less use than the common labourer,
if I did not believe that my philosophy will restore to all men the
common rights of humanity." 2
The sublimity of the starry heavens and the imperative of
the moral law are ever present influences on the life of man ;
and they require for their apprehension no previous initiation
through science and philosophy. The naked eye reveals the
former ; of the latter all men are immediately aware. 3 In
their universal appeal they are of the very substance of human
existence. Philosophy may avail to counteract the hindrances
which prevent them from exercising their native influence ; it
cannot be a substitute for the inspiration which they alone
1 Cf. Kant's Preface to the Critique of Practical Reason, W. v. p. 8 n. :
Abbott's trans, p. 93 n. " A reviewer who wanted to find some fault with this
work [the Foundations of the Metaphysics of Morals} has hit the truth better,
perhaps, than he thought, when he says that no new principle of morality is set
forth in it, but only a new formula. But who would think of introducing a new
principle of all morality, and making himself as it were the first inventor
of it, just as if all the world before him were ignorant what duty was, or had been
in thorough-going error ? But whoever knows of what importance to a mathe-
matician a formula is, which defines accurately what is to be done to work out a
problem, will not think that a formula is insignificant and useless which does the
same for all duty in general." Cf. Fortschritte, Werke (Hartenstein), viii. p. 563.
2 Fragmente aus dem Nachlasse, Werke (Hartenstein), viii. p. 624, already
quoted above, p. Ivii. Cf. also op. cit. p. 630.
3 Cf. Critique of Practical Reason, Conclusion, W. v. pp. 161-2 : Abbott's
trans, p. 260.
THE ARCHITECTONIC OF PURE REASON 1
Adickes 2 very justly remarks that " this is a section after
Kant's own heart, in which there is presented, almost un-
sought, the opportunity, which he elsewhere so frequently
creates for himself, of indulging in his favourite hobby."
The section is of slight scientific importance, and is chiefly
of interest for the light which it casts upon Kant's personality.
Moreover the distinctions which Kant here draws are for
the most part not his own philosophical property, but are
taken over from the WolrBan system.
The distinctions may be exhibited in tabular form as
follows : 3
1 A 832 = 6 860. 2 K. p. 633 n. Cf. above, p. xxii.
3 Cf. Adickes, K. p. 635 n., and Vaihinger, i. p. 306. In this table Critique
is distinguished from the System of pure Reason (cf. above, pp. 71-2). The
transcendental philosophy of pure Reason of this table corresponds to the Analytic
of the Critique, and to "pure natural science" in the absolute sense (cf. above,
pp. 66-7). The rational physics of this table corresponds to the Metaphysical
First Principles of Natural Science.
| f j
(tio ex princ
; concepts) :
i , < ..
(3 rt C
<U >>H O
g Qj ^* fl^ ^"
qj PH ^ ri
t- ^_> O OH O
0) ,} o> '3 S 4
5 ,- 3 "
M "i3 O 1/5 o
"rt -^ *rt gj
11 II '
THE TRANSCENDENTAL METHODOLOGY 581
Kant further distinguishes between the " scholastic " and
the " universal " or traditional meaning of the term philo-
sophy. 1 In the former sense philosophy is viewed from the
point of view of its logical perfection, and the philosopher
appears as an artist of Reason. 2 Philosophy in the broader
and higher sense is " the science of the relation of all know-
ledge to the essential ends of human Reason." 3 The philo-
sopher then appears as the lawgiver of human Reason. Of
the essential ends, the ultimate end is man's moral destiny ;
to this the other essential ends of human Reason are subordi-
nate means. For though the legislation of human Reason
concerns nature as well as freedom, and has therefore to be
dealt with by a philosophy of nature, i.e. of all that is, as well
as by a philosophy of morals, i.e. of that which ought to be,
the former is subordinate to the latter in the same degree in
which in human life knowledge is subordinate to moral action.
Whereas speculative metaphysics serves rather to ward off
errors than to extend knowledge, 4 in the metaphysics of
morals "all culture \Kultur\ of human Reason" 5 finds its
Empirical psychology is excluded from the domain of
metaphysics. It is destined to form part of a complete
system of anthropology, the pendant to the empirical doctrine
of nature. 6
1 I.e. between the conception of philosophy as Schulbegriff and as Weltbegriff
(conceptus cosmicus}. He explains in a note to A 839 = 6 868 that he employs
these latter terms as indicating that philosophy in the traditional or humanistic
sense is concerned with "that which must necessarily interest every one."
I have translated Weltbegriff 'as ' universal concept.' By conceptiis cosmicus Kant
means ' concept shared by the whole world/ or ' common to all mankind.'
a Cf. Kant's Logic, Introduction, iii. : Abbott's trans, pp. 14-15 : "In this
scholastic signification of the word, philosophy aims only at skill; in reference
to the higher concept common to all mankind, on the contrary, it aims
at utility. In the former aspect, therefore, it is a doctrine of skill ; in the latter
a doctrine of wisdom ; it is the lawgiver of reason ; and hence the philosopher is
not a master of the art of reason, but a lawgiver. The master of the art of reason,
or as Socrates calls him, the philodoxus, strives merely for speculative knowledge,
without concerning himself how much this knowledge contributes to the ultimate
end of human reason : he gives rules for the use of reason for all kinds of ends.
The practical philosopher, the teacher of wisdom by doctrine and example, is the
true philosopher. For philosophy is the Ideal of a perfect wisdom, which shows
us the ultimate ends of all human reason."
3 A 839 = 6867. 4 A 851 = 6879. 5 A 850 = 6878.
6 A 848-9 = 6 876-7. Cf. above, pp. 237^ 311 ., 312 ., 384-5, 473-7, 554.
THE HISTORY OF PURE REASON 1
This title, as Kant states, is inserted only to mark the
place of the present chapter in a complete system of pure
reason. The very cursory outline, which alone Kant here
attempts to give, merely repeats the main historical distinctions
of which the Critique has made use. The contrast between
the sensationalism of Epicurus and the intellectualism of
Plato has been developed in A 465 ff. = B 493 ff. 2 The contrast
between Locke and Leibniz is dwelt upon in A 43 ff. = B 60 ff.
and A 270 ff. = B 326 ff. Under the title ' naturalist of pure
Reason* Kant is referring to the * common sense* school,
which is typically represented by Beattie. 2 In his Logic*
Kant gives a fuller account of his interpretation of the history
1 A 852=8 8&x Cfc A 313 = B 370 tt, above, pp. 498-9.
* C above, pp. xmn-xxix.
* i*ififm*, IT. : Abbott's trans, pp. 17-23.
. - >i
, .- - -
*r of the natee of
^I ". / ;" ~Ii". .';"_. : ."".r"." /' LV.-1". " .V" ," r.X"V
hid to be A? novel as the sinsaiaor.
TV - - - * .,,-. i^ ^.. _ tUP * -
inese new prooKms arose m tne louowtng manner.
Accoioing to tne ittf.Hlf^al Tiew t option naT pcopen^ be
conceived on tne analogy of JHMaan activity* It coMfts rafto
itself in exetcise, and ceavx to be. It is a
}. : - <
have any pemunence of
.- .'/. vx vvx
-. .V. . s :r
teaching, on the other hand, motion is as^ different from
human activity as matter is from mind. It is ingenerable and
indestructible. We know it only through the effect which in
some incomprehensible fashion it produces in those bodies
into which it enters, namely, their translation from one part
of space to another. That this translatory motion is called
by the same name as the power which generates it, doubtless
in some degree accounts for the fact that our understanding
of the one tends to conceal from us our entire ignorance of
the other. 1 We have only to reflect, however, in order to
realise that motion is completely mysterious in its intrinsic
dynamical nature. We cannot, for instance, profess to com-
prehend, even in the least degree, how motion, though incapable
of existing apart from matter, should yet be sufficiently
independent to be able to pass from one body to another.
Descartes, following out some of the chief consequences
of this new teaching, concluded that matter is passive and
inert, that it is distinguished neither by positive nor by
negative properties from the space which it fills, and that it
is to motion that all the articulated organisation of animate
and inanimate nature is due. Descartes failed, indeed, to
appreciate the dynamical character of motion, and by constant^
speaking as if it were reducible to the translatory motion, in
which it manifests itself, he represented it as known in all its
essential features. None the less, the rdles previously assigned
to matter and motion are, in Descartes' system, completely
reversed. Matter is subordinated to motion as the instrument
to the agency by which it is directed and shaped. On the
older view, material bodies had, through the possession of
formative and vital forces, all manner of intrinsic powers. By
the new view these composite and nondescript existences are
resolved into two elements, all the properties of which can be
quantitatively defined into a matter which is uniform and
homogeneous, and into motion whose sole effect is the transla-
tion of bodies in space. Matter is the passive and inert
substance out of which motion, by its mere mechanical powers,
can produce the whole range of material forms. .
This revolutionary change in the physical standpoint
involved restatement of the philosophical issues. But the
resulting difficulties were found thoroughly baffling. Though
Descartes and his successors were willing to adopt any
hypothesis, however paradoxical, which the facts might seem
to demand, their theories, however modified and restated,
led only deeper into a hopeless impasse. The unsolved
a For recognition of this distinction, cf. Herbert Spencer, Principles of
Psychology, vol. i., 3rd ed., pp. 620-3.
THE CARTESIAN PROBLEMS 585
problems of the Cartesian systems formed the discouraging
heritage to which Kant fell heir. If matter is always purely
material, and motion is its sole organising power, there can
be no real kinship between body and mind. The formative
and vital forces, which in the Scholastic philosophy and in
popular thought serve to maintain the appearance of continuity
between matter and mind, can no longer be credited. Motion,
which alone is left to mediate between the opposites, is purely
mechanical, and (on Descartes' view) is entirely lacking in
inner or hidden powers. The animal body is exclusively
material, and is therefore as incapable of feeling or conscious-
ness as any machine made by human hands. The bodily
senses are not ' sensitive ' ; the brain cannot think. Mental
experiences do, of course, accompany the brain -motions.
But why a sensation should thus arise when a particular
motion is caused in the brain, or how a mental resolution can
be followed by a brain state, are questions to which no satis-
factory answer can be given. The mental and the material,
the spiritual and the mechanical, fall entirely apart.
The difficulties arising out of this incomprehensibility of
the causal interrelations of mind and body are not, however,
in themselves a valid argument against a dualistic interpreta-
tion of the real. The difficulties of accounting for the causal
relation are, in essential respects, equally great even when the
interaction is between homogeneous existences. The difficulties
are due to the nature of causal action as such, not to the
character of the bodies between which it holds. This, indeed,
was clearly recognised by Descartes, and was insisted upon
by his immediate successors. The transference of motion by
impact is no less incomprehensible than the interaction of soul
and body. If motion can exist only in matter, there is no
possible method of conceiving how it can make the transition
from one discrete portion of matter to another. Causal action
is thus a problem which no philosophy can pretend to solve,
and which every philosophy, whether monistic or dualistic,
must recognise as transcending the scope of our present
It is in another and more special form that Descartes'
dualism first reveals its fatal defects, namely, in its bearing
upon the problem of sense-perception. Descartes can solve the
problem of knowledge only by first postulating the doctrine of
representative perception. That doctrine is rendered necessary
by the dualism of mind and body. Objects can be known
only mediately by means of their action upon the sense-
organs, and through the sense-organs upon the brain. The
resulting brain states are in themselves merely forms of
5 86 APPENDIX B
motion. They lead, however, in a manner which Descartes
never professes to explain, 1 to the appearance of sensations
in the mental field. Out of these sensations the mind then
constructs mental images of the distant bodies ; and it is these
mental images alone which are directly apprehended. Material
bodies are invisible and intangible ; they are knowable only
through their mental duplicates. Thus, according to the
doctrine of representative perception, each mind is segregated
in a world apart. It looks out upon a landscape which is as
mental and as truly inward as are its feelings and desires.
The apparently ultimate relation of mind knowing and object
known is rendered complex and problematic through the
distinction between mental objects and real things. Mental
objects are in all cases images merely. They exist only so
long as they are apprehended ; and they are numerically and
existentially distinct in each individual mind. Real things are
not immediately perceived ; they are hypothetically inferred.
To ordinary consciousness the body which acts on the sense-
organ is the object known ; when reflective consciousness is
philosophically enlightened, the object immediately known is
recognised as a merely mental image, and the external object
sinks to the level of an assumed cause.
The paradoxical character of this doctrine is accentuated
by Galileo's distinction between primary and secondary
qualities. 2 Those physical processes, which are entitled light
and heat, bear no resemblance to the sensations through which
they become known. The many-coloured world of ordinary
consciousness is an illusory appearance which can exist only
in the human mind. We must distinguish between the
sensible world which, though purely mental, appears, through
an unavoidable illusion, to be externally real, and that very
different world of matter and motion which reveals its inde-
pendent nature only to reflective thinking. In the latter
world the rich variety of sensuous appearance can find no
place. There remain only the quantitative, mechanical pro-
perties of extension, figure and motion ; and even these have
to be interpreted in the revolutionary fashion of physical
The doctrine of representative perception cannot, however,
defend successfully the positions which it thus involves. It
wavers in unstable equilibrium. The facts, physical and
physiological, upon which it is based, are in conflict with the
conclusions in which it results. This has been very clearly
1 Cf. Studies in the Cartesian Philosophy \ pp. 80-2, 106-7.
2 This distinction is due to Galileo, though the terms "primary" and
secondary " were first employed by Locke.
THE CARTESIAN PROBLEMS 587
demonstrated by many writers in recent times. 1 The con-
flict manifested itself in the period between Descartes and
Kant only through the uneasy questionings of Locke and
Berkeley. The problem, fundamental though it be, is almost
completely ignored by Spinoza, Leibniz, and Wolff.
Stated in modern terms, the inherently contradictory
character of the doctrine consists in its unavoidable alterna-
tion between the realist attitude to which it owes its origin,
and the idealist conclusion in which it issues. Such oscilla-
tion is due to the twofold simultaneous relation in which
it regards ideas as standing to the objects that they are
supposed to represent. The function of sensations is cogni-
tive ; their origin is mechanical. As cognitive they stand to
objects in a relation of inclusion ; they reveal the objects,
reduplicating them in image before the mind. Yet in their
origin they are effects, mechanically generated by the action
of material bodies upon the sense-organs and brain. As they
are effects mechanically generated, there is no guarantee that
they resemble their causes ; and if we may argue from other
forms of mechanical causation, there is little likelihood that
they do. They stand to their first causes in a relation of
exclusion, separated from them by a large number of varying
intermediate processes. There is thus a conflict between the
function of sensations and their origin. Their origin in the
external objects is supposed to confer upon them a repre-
sentative power ; and yet the very nature of this origin
invalidates any such claim.
This irreconcilability of the subjectivist consequences of
the doctrine with its realist basis was seized upon by Berkeley.
To remove the contradiction, he denied the facts from which
the doctrine had been developed. That is to say, starting
from its results he disproved its premisses. Arguing from the
physical and physiological conditions of perception Descartes
had concluded that only sensations can be directly appre-
hended by the mind. Berkeley starts from this conclusion,
and virtually adopts it as an assumption which cannot be
questioned, and which does not call for proof. Since, he
contends, we know only sensations, the assertion that they
are due to material causes is mere hypothesis, and is one for
which there may be no valid grounds. As Descartes himself
had already suggested, there is a second possible method of
interpreting the relevant facts. There may exist an all-
1 I have dealt with Avenarius' criticism in " Avenarius' Philosophy of Pure
Experience" (Mind, vol. xv. N.S., pp. 13-31, 149-160); with Bergson's
criticism in "Subjectivism and Realism in Modern Philosophy" (Philosophical
Review, vol. xvii. pp. 138-148) ; and with the general issue as a whole in "The
Problem of Knowledge" (Journal of Philosophy, vol. ix. pp. 113-128).
powerful Being who produces the sensations in our minds
from moment to moment ; and provided that they are pro-
duced in the same order as now, the whole material world
might be annihilated without our being in the least aware
that so important an event had taken place. Since we can
experience only sensations, any hypothesis which will account
for the order of their happening is equally legitimate. The
whole question becomes one of relative simplicity in the ex-
planation given. The simpler analysis, other things being
equal, must hold the field.
Berkeley reinforces this argument by pointing to the many
embarrassing consequences to which Descartes' dualism must
lead. We postulate bodies in order to account for the origin
of our sensations, and yet are unable to do so by their means.
The dualistic theory creates more difficulties than it solves,
without a single counter-advantage, save perhaps so Berkeley
argues that it seems to harmonise better with the traditional
prejudices of the philosophic consciousness.
If we grant Berkeley his premisses, the main lines of his
argument are fairly cogent, however unconvincing may be his
own positive views. The crux, however, of the Berkeleian
idealism lies almost exclusively in the establishment of its
fundamental assumption, that only ideas (i.e. images) can be
known by the mind. This assumption Berkeley, almost
without argument, takes over from his predecessors. It was
currently accepted, and from it, therefore, he believed that he
could safely argue. It rests, however, upon the assumption
of facts which he himself questions. In rejecting the Cartesian
dualism he casts down the ladder by which alone it is possible
to climb into his position. For save through the facts of
physics and physiology there seems to be no possible method
of disproving the belief of ordinary consciousness, that in
perception we apprehend independent material bodies. And
until that belief can be shown to be false and ungrounded, the
Berkeleian idealism is without support. It cannot establish
the fundamental assumption upon which its entire argument
proceeds. Thus, though Berkeley convincingly demonstrates
the internal incoherence of the doctrine of representative per-
ception the inconsistency of its conclusions with the physical
and physiological facts upon which alone it can be based-
he cannot himself solve the problem in answer to which that
doctrine was propounded. His services, like those of so many
other reformers, were such as he did not himself foresee. In
simplifying the problem, he prepared the way for the more
sceptical treatment of its difficult issues by Hume.
At this point, in the philosophy of Hume, the problem of
THE CARTESIAN PROBLEMS 589
perception comes into the closest possible connection with
the logical problem, referred to above. The question, how
mind knowing is related to the objects known, is found to
depend upon the question, how in certain crucial cases pre-
dicates may legitimately be referred to their subject. This
logical problem arises in two forms, a narrower and a wider.
The narrower issue concerns only the principle of causality.
With what right do we assert that every event must have
a cause ? What is the ground which justifies us in thus
predicating of events a causal character ? Obviously, this
logical question is fundamental, and must be answered before
we can hope to solve the more special problem, as to our right
to interpret sensations as effects of material bodies. Hume
was the first to emphasise the vital interconnection of these