III.
ANALOGIES OF EXPERIENCE.
The principle of these is: Experience is possible only through the representation of a necessary
connection of Perceptions.
PROOF.
Experience is an empirical cognition; that is to say, a cognition
which determines an object by means of perceptions. It is therefore
a synthesis of perceptions, a synthesis which is not itself
contained in perception, but which contains the synthetical unity of
the manifold of perception in a consciousness;
and this unity
constitutes the essential of our cognition of
objects of the senses,
that is, of experience (not merely of intuition or sensation). Now
in experience our perceptions come together contingently, so that no
character of necessity in their connection appears, or can appear from
the perceptions themselves, because apprehension is only a placing
together of the manifold of empirical intuition, and no representation
of a necessity in the connected existence of the phenomena which
apprehension brings together, is to be discovered therein. But as
experience is a cognition of objects by means of perceptions, it
follows that the relation of the existence of the existence of the
manifold must be represented in experience not as it is put together
in time, but as it is objectively in time. And as time itself cannot
be perceived, the determination of the existence of objects in time
can only take place by means of their connection in time in general,
consequently only by means of
a priori connecting conceptions. Now
as these conceptions always possess the character of necessity,
experience is possible only by means of a representation of the
necessary connection of perception.
The three modi of time are permanence, succession, and
coexistence. Accordingly, there are three rules of all relations of
time in phenomena, according to which the existence of every
phenomenon is determined in respect of the unity of all time, and
these antecede all experience and render it possible.
The general principle of all three analogies rests on the
necessary unity of apperception in relation to all possible
empirical consciousness (perception) at every time, consequently, as
this unity lies a priori at the foundation of all mental operations,
the principle rests on the synthetical unity of all phenomena
according to their relation in time. For the original apperception
relates to our internal sense (the complex of all representations),
and indeed relates a priori to its form, that is to say, the
relation of the manifold empirical consciousness in time. Now this
manifold must be combined in original apperception according to
relations of time— a necessity imposed by the a priori
transcendental unity of apperception, to which is subjected all that
can belong to my (i.e., my own) cognition, and therefore all that
can become an object for me. This synthetical and a priori
determined
unity in relation of perceptions in time is therefore the
rule: "All empirical determinations of time must be subject to rules
of the general determination of time"; and the analogies of
experience, of which we are now about to treat, must be rules of
this nature.
These principles have this peculiarity, that they do not concern
phenomena, and the synthesis of the empirical intuition thereof, but
merely the existence of phenomena and their relation to each other
in regard to this existence. Now the mode in which we apprehend a
thing in a phenomenon can be determined a priori in such a manner that
the rule of its synthesis can give, that is to say, can produce this a priori
intuition in every empirical example. But the existence of
phenomena cannot be known a priori, and although we could arrive by
this path at a conclusion of the fact of some existence, we could
not cognize that existence determinately, that is to say, we should be
incapable of anticipating in what respect the empirical intuition of
it would be distinguishable from that of others.
The two principles above mentioned, which I called mathematical,
in consideration of the fact of their authorizing the application of
mathematic phenomena, relate to these phenomena only in regard to
their possibility, and instruct us how phenomena, as far as regards
their intuition or the real in their perception, can be generated
according to the rules of a mathematical synthesis. Consequently,
numerical quantities, and with them the determination of a
phenomenon as a quantity, can be employed in the one case as well as
in the other. Thus, for example, out of 200,000 illuminations by the
moon, I might compose and give a priori, that is construct, the degree
of our sensations of the sun—light.* We may therefore entitle these
two principles constitutive.
[*]
Kant's meaning is: The two principles enunciated under the heads of "Axioms of Intuition,"
and "Anticipations of Perception," authorize the application to phænomena of determinations of size and
number, that is, of mathematic. For example, I may compute the light of the sun, and say, that its
quantity is a certain number of times greater than that of the moon. In the same way, heat is measured by
the comparison of its different effects on water, &c., and on mercury in a thermometer. — Tr.
The case is very different with those principles whose province it
is to subject the existence of phenomena to rules a priori. For as
existence does not admit of being constructed,
it is clear that they
must only concern the relations of existence and be merely
regulative principles. In this case, therefore, neither axioms nor
anticipations are to be thought of. Thus, if a perception is given us,
in a certain relation of time to other (although undetermined)
perceptions, we cannot then say
a priori,
what and
how great (in
quantity) the other perception necessarily connected with the former
is, but only
how it is connected,
quoad its existence, in this given
modus of time. Analogies in philosophy mean something very different
from that which they represent in mathematics. In the latter they
are formulæ, which enounce the equality of two relations of quantity,
*
and are always
constitutive, so that if two terms of the proportion
are given, the third is also given, that is, can be constructed by the
aid of these formulæ. But in philosophy, analogy is not the
equality of two
quantitative but of two
qualitative relations. In this
case, from three given terms, I can give
a priori and cognize the
relation to a fourth member,
* but not this fourth term itself, although
I certainly possess a rule to guide me in the search for this fourth
term in experience, and a mark to assist me in discovering it. An
analogy of experience is therefore only a rule according to which
unity of experience must arise out of perceptions in respect to
objects (phenomena) not as a
constitutive, but merely as a
regulative principle. The same holds good also of the postulates of
empirical thought in general, which relate to the synthesis of mere
intuition (which concerns the form of phenomena), the synthesis of
perception (which concerns the matter of phenomena), and the synthesis
of experience (which concerns the relation of these perceptions).
For they are only regulative principles, and clearly distinguishable
from the mathematical, which are constitutive, not indeed in regard to
the certainty which both
possess
a priori, but in the mode of evidence
thereof, consequently also in the manner of demonstration.
[*]
Known the two terms 3 and 6, and the relation of 3 to 6, not only the relation of 6
to some other number is given, but that number itself, 12, is given, that is, it is constructed.
Therefore 3 : 6 = 6 : 12. — Tr.
[*]
Given a known effect, a known cause, and another known effect, we reason, by analogy,
to an unknown cause, which we do not cognize, but whose relation to the known effect we know from the
comparison of the three given terms. Thus, our own known actions : our own known motives = the known
actions of others : x, that is, the motives of others which we cannot immediately cognize. — Tr.
But what has been observed of all synthetical propositions, and must
be particularly remarked in this place, is this, that these
analogies possess significance and validity, not as principles of
the transcendental, but only as principles of the empirical use of the
understanding, and their truth can therefore be proved only as such,
and that consequently the phenomena must not be subjoined directly
under the categories, but only under their schemata. For if the
objects to which those principles must be applied were things in
themselves, it would be quite impossible to cognize aught concerning
them synthetically a priori. But they are nothing but phenomena; a
complete knowledge of which— a knowledge to which all principles a priori
must at last relate— is the only possible experience. It
follows that these principles can have nothing else for their aim than
the conditions of the empirical cognition in the unity of synthesis of
phenomena. But this synthesis is cogitated only in the schema of the
pure conception of the understanding, of whose unity, as that of a
synthesis in general, the category contains the function
unrestricted by any sensuous condition. These principles will
therefore authorize us to connect phenomena according to an analogy,
with the logical and universal unity of conceptions, and
consequently to employ the categories in the principles themselves;
but in the application of them to experience, we shall use only
their schemata, as the key to their proper application, instead of the
categories, or rather the latter as restricting conditions, under
the title of "formulæ" of the former.
A.
FIRST ANALOGY.
Principle of the Permanence of Substance.
In all changes of phenomena, substance is permanent, and
the quantum thereof in nature is neither increased nor diminished.
PROOF.
All phenomena exist in time, wherein alone as substratum, that is,
as the permanent form of the internal intuition, coexistence and
succession can be represented. Consequently
time, in which all changes
of phenomena must be cogitated, remains and changes not, because it is
that in which succession and coexistence can be represented only as
determinations thereof. Now, time in itself cannot be an object of
perception. It follows that in objects of perception, that is, in
phenomena, there must be found a substratum which represents time in
general, and in which all change or coexistence can be perceived by
means of the relation of phenomena to it. But the substratum of all
reality, that is, of all that pertains to the existence of things,
is substance; all that pertains to existence can be cogitated only
as a determination of substance. Consequently, the permanent, in
relation to which alone can all relations of time in phenomena be
determined, is substance in the world of phenomena, that is, the
real in phenomena, that which, as the substratum of all change,
remains ever the same. Accordingly, as this cannot change in
existence, its quantity in nature can neither be increased nor
diminished.
Our apprehension of the manifold in a phenomenon is always
successive, is Consequently always changing. By it alone we could,
therefore, never determine whether this manifold, as an object of
experience, is coexistent or successive, unless it had for a
foundation something that exists always, that is, something fixed and permanent, of the existence of which
all succession and coexistence are nothing but so many modes (modi
of time). Only in the permanent, then, are relations of time
possible (for simultaneity and succession are the only relations in
time); that is to say, the permanent is the substratum of our
empirical representation of time itself, in which alone all
determination of time is possible. Permanence is, in fact, just
another expression for time, as the abiding correlate of all existence
of phenomena, and of all change, and of all coexistence. For change
does not affect time itself, but only the phenomena in time (just as
coexistence cannot be regarded as a modus of time itself, seeing
that in time no parts are coexistent, but all successive).* If we
were to attribute succession to time itself, we should be obliged to
cogitate another time, in which this succession would be possible.
It is only by means of the permanent that existence
in different parts
of the successive series of time receives a
quantity, which we entitle
duration. For in mere succession, existence is perpetually vanishing
and recommencing, and therefore never has even the least quantity.
Without the permanent, then, no relation in time is possible. Now,
time in itself is not an object of perception; consequently the
permanent in phenomena must be regarded as the substratum of all
determination of time, and consequently also as the condition of the
possibility of all synthetical unity of perceptions, that is, of
experience; and all existence and all change in time can only be
regarded as a mode in the existence of that which abides unchangeably.
Therefore, in all phenomena, the permanent is the object
in itself,
that is, the substance (phenomenon);
* but all that changes or can
change belongs only to the mode of the existence of this substance
or substances, consequently to its determinations.
[*]
The latter part of this sentence seems to contradict the former. The sequel will
explain. — Tr.
[*]
Not substantia noumenon. — Tr.
I find that in all ages not only the philosopher, but even the
common understanding, has preposited this permanence as a substratum
of all change in phenomena; indeed, I am compelled to believe that
they will always accept this as an indubitable fact. Only the
philosopher expresses himself in a more precise and definite manner,
when he says: "In all changes in the world, the substance remains, and
the accidents alone are changeable." But of this decidedly synthetical
proposition, I nowhere meet with even an attempt at proof; nay, it
very rarely has the good fortune to stand, as it deserves to do, at
the head of the pure and entirely a priori laws of nature. In truth,
the statement that substance is permanent, is tautological. For this
very permanence is the ground on which we apply the category of
substance to the phenomenon; and we should have been obliged to
prove that in all phenomena there is something permanent, of the
existence of which the changeable is nothing but a determination.
But because a proof of this nature cannot be dogmatical, that is,
cannot be drawn from conceptions, inasmuch as it concerns a
synthetical proposition a priori, and as philosophers never
reflected that such propositions are valid only in relation to
possible experience, and therefore cannot be proved except by means of
a deduction of the possibility of experience, it is no wonder that
while it has served as the foundation of all experience
(for we feel
the need of it in empirical cognition), it has never been supported by
proof.
A philosopher was asked: "What is the weight of smoke?" He answered:
"Subtract from the weight of the burnt wood the weight of the
remaining ashes, and you will have the weight of the smoke." Thus he
presumed it to be incontrovertible that even in fire the matter
(substance) does not perish, but that only the form of it undergoes
a change. In like manner was the saying: "From nothing comes nothing,"
only another inference from the principle or permanence, or rather
of the ever—abiding existence of the true subject in phenomena. For if
that in the phenomenon which we call substance is to be the proper
substratum of all determination of time, it follows that all existence
in past as well as in future time, must be determinable by means of it
alone. Hence we are entitled to apply the term substance to a
phenomenon, only because we suppose its existence in all time, a
notion which the word permanence does not fully express, as it seems
rather to be referable to future time. However, the internal necessity
perpetually to be, is inseparably connected with the necessity
always to have been, and so the expression may stand as it is.
"Gigni de nihilo nihil," — "in nihilum nil posse reverti," are two
propositions which the ancients never parted, and which people
nowadays sometimes mistakenly disjoin, because they imagine that the
propositions apply to objects as things in themselves, and that the
former might be inimical to the dependence (even in respect of its
substance also) of the world upon a supreme cause. But this
apprehension is entirely needless, for the question in this case is
only of phenomena in the sphere of experience, the unity of which
never could be possible, if we admitted the possibility that new
things (in respect of their substance) should arise. For in that case,
we should lose altogether that which alone can represent the unity
of time, to wit, the identity of the substratum, as that through which
alone all change possesses complete and thorough unity. This
permanence is, however, nothing but the manner in which we represent
to ourselves the existence of things in the phenomenal world.
The determinations of a substance, which are only particular modes
of its existence, are called accidents. They are always real,
because they concern the existence of substance
(negations are only
determinations, which express the non—existence of something in the
substance). Now, if to this real in the substance we ascribe a
particular existence (for example, to motion as an accident of
matter), this existence is called inherence, in contradistinction to
the existence of substance, which we call subsistence. But hence arise
many misconceptions, and it would be a more accurate and just mode
of expression to designate the accident only as the mode in which
the existence of a substance is positively determined. Meanwhile, by
reason of the conditions of the logical exercise of our understanding,
it is impossible to avoid separating, as it were, that which in the
existence of a substance is subject to change, whilst the substance
remains, and regarding it in relation to that which is properly
permanent and radical. On this account, this category of substance
stands under the title of relation, rather because it is the condition
thereof than because it contains in itself any relation.
Now, upon this notion of permanence rests the proper notion of the
conception change. Origin and extinction are not changes of that which
originates or becomes extinct. Change is but a mode of existence,
which follows on another mode of existence of the same object; hence
all that changes is permanent, and only the condition thereof changes.
Now since this mutation affects only determinations, which can have
a beginning or an end, we may say, employing an expression which seems
somewhat paradoxical: "Only the permanent (substance) is subject to
change; the mutable suffers no change, but rather alternation, that
is, when certain determinations cease, others begin."
Change, when, cannot be perceived by us except in substances, and
origin or extinction in an absolute sense, that does not concern
merely a determination of the permanent, cannot be a possible
perception, for it is this very notion of the permanent which
renders possible the representation of a transition from one state
into another, and from non—being to being, which, consequently, can be
empirically cognized only as alternating determinations of that
which is permanent. Grant that a thing absolutely begins to be; we
must then have a point of time in which it was not. But how and by
what can we fix and determine this point of time, unless by that which
already exists? For a void time— preceding—
is not an object of
perception; but if we connect this beginning with objects which
existed previously, and which continue to exist till the object in
question in question begins to be, then the latter can only be a
determination of the former as the permanent. The same holds good of
the notion of extinction, for this presupposes the empirical
representation of a time, in which a phenomenon no longer exists.
Substances (in the world of phenomena) are the substratum of all
determinations of time. The beginning of some, and the ceasing to be
of other substances, would utterly do away with the only condition
of the empirical unity of time; and in that case phenomena would
relate to two different times, in which, side by side, existence would
pass; which is absurd. For there is only one time in which all
different times must be placed, not as coexistent, but as successive.
Accordingly, permanence is a necessary condition under which alone
phenomena, as things or objects, are determinable in a possible
experience. But as regards the empirical criterion of this necessary
permanence, and with it of the substantiality of phenomena, we shall
find sufficient opportunity to speak in the sequel.
B.
SECOND ANALOGY.
PRINCIPLE OF THE SUCCESSION OF TIME ACCORDING TO THE
LAW OF CAUSALITY.
All changes take place according to the law of the connection of Cause and Effect.
PROOF.
(That all phenomena in the succession of time are only changes, that
is, a successive being and non—being of the determinations of
substance, which is permanent; consequently that a being of
substance itself which follows on the non—being thereof, or a
non—being of substance which follows on the being thereof, in other
words, that the origin or extinction of substance itself, is
impossible— all this has been fully established in treating of the
foregoing principle. This principle might have been expressed as
follows: "All alteration (succession) of phenomena is merely
change"; for the changes
of substance are not origin or extinction,
because the conception of change presupposes the same subject as
existing with two opposite determinations, and consequently as
permanent. After this premonition, we shall proceed to the proof.)
I perceive that phenomena succeed one another, that is to say, a
state of things exists at one time, the opposite of which existed in a
former state. In this case, then, I really connect together two
perceptions in time. Now connection is not an operation of mere
sense and intuition, but is the product of a synthetical faculty of
imagination, which determines the internal sense in respect of a
relation of time. But imagination can connect these two states in
two ways, so that either the one or the other may antecede in time;
for time in itself cannot be an object of perception, and what in an
object precedes and what follows cannot be empirically determined in
relation to it. I am only conscious, then, that my imagination
places one state before and the other after; not that the one state
antecedes the other in the object. In other words, the objective
relation of the successive phenomena remains quite undetermined by
means of mere perception. Now in order that this relation may be
cognized as determined, the relation between the two states must be so
cogitated that it is thereby determined as necessary, which of them
must be placed before and which after, and not conversely. But the
conception which carries with it a necessity of synthetical unity, can
be none other than a pure conception of the understanding which does
not lie in mere perception; and in this case it is the conception of
"the relation of cause and effect," the former of which determines the
latter in time, as its necessary consequence, and not as something
which might possibly antecede (or which might in some cases not be
perceived to follow). It follows that it is only because we subject
the sequence of phenomena, and consequently all change, to the law
of causality, that experience itself, that is, empirical cognition
of phenomena, becomes possible; and consequently, that phenomena
themselves, as objects of experience, are possible only by virtue of
this law.
Our apprehension of the manifold of phenomena is always
successive. The representations of parts succeed one another.
Whether they succeed one another in the object also, is a second point
for reflection, which was not contained in the former.
Now we may
certainly give the name of object to everything, even to every
representation, so far as we are conscious thereof; but what this word
may mean in the case of phenomena, not merely in so far as they (as
representations) are objects, but only in so far as they indicate an
object, is a question requiring deeper consideration. In so far as
they, regarded merely as representations, are at the same time objects
of consciousness, they are not to be distinguished from
apprehension, that is, reception into the synthesis of imagination,
and we must therefore say: "The manifold of phenomena is always
produced successively in the mind." If phenomena were things in
themselves, no man would be able to conjecture from the succession
of our representations how this manifold is connected in the object;
for we have to do only with our representations. How things may be
in themselves, without regard to the representations through which
they affect us, is utterly beyond the sphere of our cognition. Now
although phenomena are not things in themselves, and are
nevertheless the only thing given to us to be cognized, it is my
duty to show what sort of connection in time belongs to the manifold
in phenomena themselves, while the representation of this manifold
in apprehension is always successive. For example, the apprehension of
the manifold in the phenomenon of a house which stands before me, is
successive. Now comes the question whether the manifold of this
house is in itself successive— which no one will be at all willing
to grant. But, so soon as I raise my conception of an object to the
transcendental signification thereof, I find that the house is not a
thing in itself, but only a phenomenon, that is, a representation, the
transcendental object of which remains utterly unknown. What then am I
to understand by the question: "How can the manifold be connected in
the phenomenon itself— not considered as a thing in itself, but merely
as a phenomenon?" Here that which lies in my successive apprehension
is regarded as representation, whilst the phenomenon which is given
me, notwithstanding that it is nothing more than a complex of these
representations, is regarded as the object thereof, with which my
conception, drawn from the representations of apprehension, must
harmonize. It is very soon seen that, as accordance of the cognition
with its object constitutes truth, the question now before us can only
relate to the formal conditions of empirical truth;
and that the
phenomenon, in opposition to the representations of apprehension,
can only be distinguished therefrom as the object of them, if it is
subject to a rule which distinguishes it from every other
apprehension, and which renders necessary a mode of connection of
the manifold. That in the phenomenon which contains the condition of
this necessary rule of apprehension, is the object.
Let us now proceed to our task. That something happens, that is to
say, that something or some state exists which before was not,
cannot be empirically perceived, unless a phenomenon precedes, which
does not contain in itself this state. For a reality which should
follow upon a void time, in other words, a beginning, which no state
of things precedes, can just as little be apprehended as the void time
itself. Every apprehension of an event is therefore a perception which
follows upon another perception. But as this is the case with all
synthesis of apprehension, as I have shown above in the example of a
house, my apprehension of an event is not yet sufficiently
distinguished from other apprehensions. But I remark also that if in a
phenomenon which contains an occurrence, I call the antecedent state
of my perception, A, and the following state, B, the perception B
can only follow A in apprehension, and the perception A cannot
follow B, but only precede it. For example, I see a ship float down
the stream of a river. My perception of its place lower down follows
upon my perception of its place higher up the course of the river, and
it is impossible that, in the apprehension of this phenomenon, the
vessel should be perceived first below and afterwards higher up the
stream. Here, therefore, the order in the sequence of perceptions in
apprehension is determined; and by this order apprehension is
regulated. In the former example, my perceptions in the apprehension
of a house might begin at the roof and end at the foundation, or
vice versa; or I might apprehend the manifold in this empirical
intuition, by going from left to right, and from right to left.
Accordingly, in the series of these perceptions, there was no
determined order, which necessitated my beginning at a certain
point, in order empirically to connect the manifold. But this rule
is always to be met with in the perception of that which happens,
and it makes the order of the successive perceptions in the
apprehension of such a phenomenon necessary.
I must, therefore, in the present case, deduce the subjective
sequence of apprehension from the objective sequence of phenomena, for
otherwise the former is quite undetermined, and one phenomenon is
not distinguishable from another. The former alone proves nothing as
to the connection of the manifold in an object, for it is quite
arbitrary. The latter must consist in the order of the manifold in a
phenomenon, according to which order the apprehension of one thing
(that which happens) follows that of another thing (which precedes),
in conformity with a rule. In this way alone can I be authorized to
say of the phenomenon itself, and not merely of my own apprehension,
that a certain order or sequence is to be found therein. That is, in
other words, I cannot arrange my apprehension otherwise than in this
order.
In conformity with this rule, then, it is necessary that in that
which antecedes an event there be found the condition of a rule,
according to which in this event follows always and necessarily; but I
cannot reverse this and go back from the event, and determine (by
apprehension) that which antecedes it. For no phenomenon goes back
from the succeeding point of time to the preceding point, although
it does certainly relate to a preceding point of time; from a given
time, on the other hand, there is always a necessary progression to
the determined succeeding time. Therefore, because there certainly
is something that follows, I must of necessity connect it with
something else, which antecedes, and upon which it follows, in
conformity with a rule, that is necessarily, so that the event, as
conditioned, affords certain indication of a condition, and this
condition determines the event.
Let us suppose that nothing precedes an event, upon which this event
must follow in conformity with a rule. All sequence of perception
would then exist only in apprehension, that is to say, would be merely
subjective, and it could not thereby be objectively determined what
thing ought to precede, and what ought to follow in perception. In
such a case, we should have nothing but a play of representations,
which would possess no application to any object. That is to say, it
would not be possible through perception to distinguish one phenomenon
from another, as regards relations of time; because the succession
in the act of apprehension would always be of the same
sort, and
therefore there would be nothing in the phenomenon to determine the
succession, and to render a certain sequence objectively necessary.
And, in this case, I cannot say that two states in a phenomenon follow
one upon the other, but only that one apprehension follows upon
another. But this is merely subjective, and does not determine an
object, and consequently cannot be held to be cognition of an
object— not even in the phenomenal world.
Accordingly, when we know in experience that something happens, we
always presuppose that something precedes, whereupon it follows in
conformity with a rule. For otherwise I could not say of the object
that it follows; because the mere succession in my apprehension, if it
be not determined by a rule in relation to something preceding, does
not authorize succession in the object. Only, therefore, in
reference to a rule, according to which phenomena are determined in
their sequence, that is, as they happen, by the preceding state, can I
make my subjective synthesis (of apprehension) objective, and it is
only under this presupposition that even the experience of an event is
possible.
No doubt it appears as if this were in thorough contradiction to all
the notions which people have hitherto entertained in regard to the
procedure of the human understanding. According to these opinions,
it is by means of the perception and comparison of similar
consequences following upon certain antecedent phenomena that the
understanding is led to the discovery of a rule, according to which
certain events always follow certain phenomena, and it is only by this
process that we attain to the conception of cause. Upon such a
basis, it is clear that this conception must be merely empirical,
and the rule which it furnishes us with— "Everything that happens must
have a cause"— would be just as contingent as experience itself. The
universality and necessity of the rule or law would be perfectly
spurious attributes of it. Indeed, it could not possess universal
validity, inasmuch as it would not in this case be a priori, but
founded on deduction. But the same is the case with this law as with
other pure a priori representations (e.g., space and time), which we
can draw in perfect clearness and completeness from experience, only
because we had already placed them therein, and by that means, and
by that alone, had rendered experience possible.
Indeed, the logical
clearness of this representation of a rule, determining the series
of events, is possible only when we have made use thereof in
experience. Nevertheless, the recognition of this rule, as a condition
of the synthetical unity of phenomena in time, was the ground of
experience itself and consequently preceded it
a priori.
It is now our duty to show by an example that we never, even in
experience, attribute to an object the notion of succession or
effect (of an event— that is, the happening of something that did
not exist before), and distinguish it from the subjective succession
of apprehension, unless when a rule lies at the foundation, which
compels us to observe this order of perception in preference to any
other, and that, indeed, it is this necessity which first renders
possible the representation of a succession in the object.
We have representations within us, of which also we can be
conscious. But, however widely extended, however accurate and
thoroughgoing this consciousness may be, these representations are
still nothing more than representations, that is, internal
determinations of the mind in this or that relation of time. Now how
happens it that to these representations we should set an object, or
that, in addition to their subjective reality, as modifications, we
should still further attribute to them a certain unknown objective
reality? It is clear that objective significancy cannot consist in a
relation to another representation (of that which we desire to term
object), for in that case the question again arises: "How does this
other representation go out of itself, and obtain objective
significancy over and above the subjective, which is proper to it,
as a determination of a state of mind?" If we try to discover what
sort of new property the relation to an object gives to our subjective
representations, and what new importance they thereby receive, we
shall find that this relation has no other effect than that of
rendering necessary the connection of our representations in a certain
manner, and of subjecting them to a rule; and that conversely, it is
only because a certain order is necessary in the relations of time
of our representations, that objective significancy is ascribed to
them.
In the synthesis of phenomena, the manifold of our representations
is always successive. Now hereby is not represented an object, for
by means of this succession, which is
common to all apprehension, no
one thing is distinguished from another. But so soon as I perceive
or assume that in this succession there is a relation to a state
antecedent, from which the representation follows in accordance with a
rule, so soon do I represent something as an event, or as a thing that
happens; in other words, I cognize an object to which I must assign
a certain determinate position in time, which cannot be altered,
because of the preceding state in the object. When, therefore, I
perceive that something happens, there is contained in this
representation, in the first place, the fact, that something
antecedes; because, it. is only in relation to this that the
phenomenon obtains its proper relation of time, in other words, exists
after an antecedent time, in which it did not exist. But it can
receive its determined place in time only by the presupposition that
something existed in the foregoing state, upon which it follows
inevitably and always, that is, in conformity with a rule. From all
this it is evident that, in the first place, I cannot reverse the
order of succession, and make that which happens precede that upon
which it follows; and that, in the second place, if the antecedent
state be posited, a certain determinate event inevitably and
necessarily follows. Hence it follows that there exists a certain
order in our representations, whereby the present gives a sure
indication of some previously existing state, as a correlate, though
still undetermined, of the existing event which is given— a
correlate which itself relates to the event as its consequence,
conditions it, and connects it necessarily with itself in the series
of time.
If then it be admitted as a necessary law of sensibility, and
consequently a formal condition of all perception, that the
preceding necessarily determines the succeeding time (inasmuch as I
cannot arrive at the succeeding except through the preceding), it must
likewise be an indispensable law of empirical representation of the
series of time that the phenomena of the past determine all
phenomena in the succeeding time, and that the latter, as events,
cannot take place, except in so far as the former determine their
existence in time, that is to say, establish it according to a rule.
For it is of course only in phenomena that we can empirically
cognize this continuity in the connection of times.
For all experience and for the possibility of experience,
understanding
is indispensable, and the first step which it takes in
this sphere is not to render the representation of objects clear,
*
but to render the representation of an object in general, possible. It
does this by applying the order of time to phenomena, and their
existence. In other words, it assigns to each phenomenon, as a
consequence, a place in relation to preceding phenomena, determined
a priori in time, without which it could not harmonize with time
itself, which determines a place
a priori to all its parts. This
determination of place cannot be derived from the relation of
phenomena to absolute time (for it is not an object of perception);
but, on the contrary, phenomena must reciprocally determine the places
in time of one another, and render these necessary in the order of
time. In other words, whatever follows or happens, must follow in
conformity with a universal rule upon that which was contained in
the foregoing state. Hence arises a series of phenomena, which, by
means of the understanding, produces and renders necessary exactly the
same order and continuous connection in the series of our possible
perceptions, as is found
a priori in the form of internal intuition
(time), in which all our perceptions must have place.
[*]
This was the opinion of Wolf and Leibnitz. — Tr.
That something happens, then, is a perception which belongs to a
possible experience, which becomes real only because I look upon the
phenomenon as determined in regard to its place in time,
consequently as an object, which can always be found by means of a
rule in the connected series of my perceptions. But this rule of the
determination of a thing according to succession in time is as
follows: "In what precedes may be found the condition, under which
an event always (that is, necessarily) follows." From all this it is
obvious that the principle of cause and effect is the principle of
possible experience, that is, of objective cognition of phenomena,
in regard to their relations in the succession of time.
The proof of this fundamental proposition rests entirely on the
following momenta of argument. To all empirical cognition belongs
the synthesis of the manifold by the imagination, a synthesis which is
always successive, that is, in which the representations therein
always follow one another. But the order of succession in
imagination is not determined, and the series of successive
representations may be taken retrogressively
as well as progressively.
But if this synthesis is a synthesis of apprehension (of the
manifold of a given phenomenon),then the order is determined in the
object, or to speak more accurately, there is therein an order of
successive synthesis which determines an object, and according to
which something necessarily precedes, and when this is posited,
something else necessarily follows. If, then, my perception is to
contain the cognition of an event, that is, of something which
really happens, it must be an empirical judgement, wherein we think
that the succession is determined; that is, it presupposes another
phenomenon, upon which this event follows necessarily, or in
conformity with a rule. If, on the contrary, when I posited the
antecedent, the event did not necessarily follow, I should be
obliged to consider it merely as a subjective play of my
imagination, and if in this I represented to myself anything as
objective, I must look upon it as a mere dream. Thus, the relation
of phenomena (as possible perceptions), according to which that
which happens is, as to its existence, necessarily determined in
time by something which antecedes, in conformity with a rule— in other
words, the relation of cause and effect— is the condition of the
objective validity of our empirical judgements in regard to the
sequence of perceptions, consequently of their empirical truth, and
therefore of experience. The principle of the relation of causality in
the succession of phenomena is therefore valid for all objects of
experience, because it is itself the ground of the possibility of
experience.
Here, however, a difficulty arises, which must be resolved. The
principle of the connection of causality among phenomena is limited in
our formula to the succession thereof, although in practice we find
that the principle applies also when the phenomena exist together in
the same time, and that cause and effect may be simultaneous. For
example, there is heat in a room, which does not exist in the open
air. I look about for the cause, and find it to be the fire, Now the
fire as the cause is simultaneous with its effect, the heat of the
room. In this case, then, there is no succession as regards time,
between cause and effect, but they are simultaneous; and still the law
holds good. The greater part of operating causes in nature are
simultaneous with their effects, and the succession in time of the
latter is produced only because
the cause cannot achieve the total
of its effect in one moment. But at the moment when the effect
first
arises, it is always simultaneous with the causality of its cause,
because, if the cause had but a moment before ceased to be, the effect
could not have arisen. Here it must be specially remembered that we
must consider the
order of time and not the
lapse thereof. The
relation remains, even though no time has elapsed. The time between
the causality of the cause and its immediate effect may entirely
vanish, and the cause and effect be thus simultaneous, but the
relation of the one to the other remains always determinable according
to time. If, for example, I consider a leaden ball, which lies upon
a cushion and makes a hollow in it, as a cause, then it is
simultaneous with the effect. But I distinguish the two through the
relation of time of the dynamical connection of both. For if I lay the
ball upon the cushion, then the hollow follows upon the before
smooth surface; but supposing the cushion has, from some cause or
another, a hollow, there does not thereupon follow a leaden ball.
Thus, the law of succession of time is in all instances the only
empirical criterion of effect in relation to the causality of the
antecedent cause. The glass is the cause of the rising of the water
above its horizontal surface, although the two phenomena are
contemporaneous. For, as soon as I draw some water with the glass from
a larger vessel, an effect follows thereupon, namely, the change of
the horizontal state which the water had in the large vessel into a
concave, which it assumes in the glass.
This conception of causality leads us to the conception of action;
that of action, to the conception of force; and through it, to the
conception of substance. As I do not wish this critical essay, the
sole purpose of which is to treat of the sources of our synthetical
cognition a priori, to be crowded with analyses which merely
explain, but do not enlarge the sphere of our conceptions, I reserve
the detailed explanation of the above conceptions for a future
system of pure reason. Such an analysis, indeed, executed with great
particularity, may already be found in well—known works on this
subject. But I cannot at present refrain from making a few remarks
on the empirical criterion of a substance, in so far as it seems to be
more evident and more easily recognized through the conception of
action than through that of the permanence of a phenomenon.
Where action (consequently activity and force) exists, substance
also must exist, and in it alone must be sought the seat of that
fruitful source of phenomena. Very well. But if we are called upon
to explain what we mean by substance, and wish to avoid the vice of
reasoning in a circle, the answer is by no means so easy. How shall we
conclude immediately from the action to the permanence of that which
acts, this being nevertheless an essential and peculiar criterion of
substance (phenomenon)? But after what has been said above, the
solution of this question becomes easy enough, although by the
common mode of procedure— merely analysing our conceptions— it would
be quite impossible. The conception of action indicates the relation
of the subject of causality to the effect. Now because all effect
consists in that which happens, therefore in the changeable, the
last subject thereof is the permanent, as the substratum of all that
changes, that is, substance. For according to the principle of
causality, actions are always the first ground of all change in
phenomena and, consequently, cannot be a property of a subject which
itself changes, because if this were the case, other actions and
another subject would be necessary to determine this change. From
all this it results that action alone, as an empirical criterion, is a
sufficient proof of the presence of substantiality, without any
necessity on my part of endeavouring to discover the permanence of
substance by a comparison. Besides, by this mode of induction we could
not attain to the completeness which the magnitude and strict
universality of the conception requires. For that the primary
subject of the causality of all arising and passing away, all origin
and extinction, cannot itself (in the sphere of phenomena) arise and
pass away, is a sound and safe conclusion, a conclusion which leads us
to the conception of empirical necessity and permanence in
existence, and consequently to the conception of a substance as
phenomenon.
When something happens, the mere fact of the occurrence, without
regard to that which occurs, is an object requiring investigation. The
transition from the non—being of a state into the existence of it,
supposing that this state contains no quality which previously existed
in the phenomenon, is a fact of itself
demanding inquiry. Such an
event, as has been shown in No. A, does not concern substance (for
substance does not thus originate), but its condition or state. It
is therefore only change, and not origin from nothing. If this
origin be regarded as the effect of a foreign cause, it is termed
creation, which cannot be admitted as an event among phenomena,
because the very possibility of it would annihilate the unity of
experience. If, however, I regard all things not as phenomena, but
as things in themselves and objects of understanding alone, they,
although substances, may be considered as dependent, in respect of
their existence, on a foreign cause. But this would require a very
different meaning in the words, a meaning which could not apply to
phenomena as objects of possible experience.
How a thing can be changed, how it is possible that upon one state
existing in one point of time, an opposite state should follow in
another point of time— of this we have not the smallest conception a priori
. There is requisite for this the knowledge of real powers,
which can only be given empirically; for example, knowledge of
moving forces, or, in other words, of certain successive phenomena (as
movements) which indicate the presence of such forces. But the form of
every change, the condition under which alone it can take place as the
coming into existence of another state (be the content of the
change, that is, the state which is changed, what it may), and
consequently the succession of the states themselves can very well
be considered a priori, in relation to the law of causality and the
conditions of time.*
[*]
It must be remarked that I do not speak of the change of certain
relations, but of the change of the state. Thus, when a body moves
in a uniform manner, it does not change its state (of motion); but
only when all motion increases or decreases.
When a substance passes from one state, a, into another state, b,
the point of time in which the latter exists is different from, and
subsequent to that in which the former existed. In like manner, the
second state, as reality (in the phenomenon), differs from the
first, in which the reality of the second did not exist, as b from
zero. That is to say, if the state, b, differs from the state, a, only
in respect to quantity, the change is a coming into existence of b —
a, which in the former state did not exist, and in relation to which
that state is = O.
Now the question arises how a thing passes from one state = a,
into another state = b. Between two moments there is always a
certain time, and between two states existing in these moments there
is always a difference having a certain quantity (for all parts of
phenomena are in their turn quantities). Consequently, every
transition from one state into another is always effected in a time
contained between two moments, of which the first determines the state
which leaves, and the second determines the state into the thing
passes. the thing leaves, and the second determines the state into
which the thing Both moments, then, are limitations of the time of a
change, consequently of the intermediate state between both, and as
such they belong to the total of the change. Now every change has a
cause, which evidences its causality in the whole time during which
the charge takes place. The cause, therefore, does not produce the
change all at once or in one moment, but in a time, so that, as the
time gradually increases from the commencing instant, a, to its
completion at b, in like manner also, the quantity of the reality
(b — a) is generated through the lesser degrees which are contained
between the first and last. All change is therefore possible only
through a continuous action of the causality, which, in so far as it
is uniform, we call a momentum. The change does not consist of these
momenta, but is generated or produced by them as their effect.
Such is the law of the continuity of all change, the ground of which
is that neither time itself nor any phenomenon in time consists of
parts which are the smallest possible, but that, notwithstanding,
the state of a thing passes in the process of a change through all
these parts, as elements, to its second state. There is no smallest
degree of reality in a phenomenon, just as there is no smallest degree
in the quantity of time; and so the new state of reality grows up
out of the former state, through all the infinite degrees thereof, the
differences of which one from another, taken all together, are less
than the difference between o and a.
It is not our business to inquire here into the utility of this
principle in the investigation of nature. But how such a
proposition, which appears so greatly to extend our knowledge of
nature, is possible completely a priori, is indeed a question which
deserves investigation, although the first view seems to demonstrate
the truth and reality of the principle, and the question,
how it is
possible, may be considered superfluous. For there are so many
groundless pretensions to the enlargement of our knowledge by pure
reason that we must take it as a general rule to be mistrustful of all
such, and without a thoroughgoing and radical deduction, to believe
nothing of the sort even on the clearest dogmatical evidence.
Every addition to our empirical knowledge, and every advance made in
the exercise of our perception, is nothing more than an extension of
the determination of the internal sense, that is to say, a progression
in time, be objects themselves what they may, phenomena, or pure
intuitions. This progression in time determines everything, and is
itself determined by nothing else. That is to say, the parts of the
progression exist only in time, and by means of the synthesis thereof,
and are not given antecedently to it. For this reason, every
transition in perception to anything which follows upon another in
time, is a determination of time by means of the production of this
perception. And as this determination of time is, always and in all
its parts, a quantity, the perception produced is to be considered
as a quantity which proceeds through all its degrees— no one of
which is the smallest possible— from zero up to its determined degree.
From this we perceive the possibility of cognizing a priori a law of
changes— a law, however, which concerns their form merely. We merely
anticipate our own apprehension, the formal condition of which,
inasmuch as it is itself to be found in the mind antecedently to all
given phenomena, must certainly be capable of being cognized a priori.
Thus, as time contains the sensuous condition a priori of the
possibility of a continuous progression of that which exists to that
which follows it, the understanding, by virtue of the unity of
apperception, contains the condition a priori of the possibility of
a continuous determination of the position in time of all phenomena,
and this by means of the series of causes and effects, the former of
which necessitate the sequence of the latter, and thereby render
universally and for all time, and by consequence, objectively, valid
the empirical cognition of the relations of time.
C.
THIRD ANALOGY.
PRINCIPLE OF COEXISTENCE, ACCORDING TO THE LAW OF
RECIPROCITY OR COMMUNITY.
All substances, in so far as they can be perceived in space at the
same time, exist in a state of complete reciprocity of action.
PROOF.
Things are coexistent, when in empirical intuition the perception of
the one can follow upon the perception of the other, and vice versa—
which cannot occur in the succession of phenomena, as we have shown in
the explanation of the second principle. Thus I can perceive the
moon and then the earth, or conversely, first the earth and then the
moon; and for the reason that my perceptions of these objects can
reciprocally follow each other, I say, they exist contemporaneously.
Now coexistence is the existence of the manifold in the same time. But
time itself is not an object of perception; and therefore we cannot
conclude from the fact that things are placed in the same time, the
other fact, that the perception of these things can follow each
other reciprocally. The synthesis of the imagination in apprehension
would only present to us each of these perceptions as present in the
subject when the other is not present, and contrariwise; but would not
show that the objects are coexistent, that is to say, that, if the one
exists, the other also exists in the same time, and that this is
necessarily so, in order that the perceptions may be capable of
following each other reciprocally. It follows that a conception of the
understanding or category of the reciprocal sequence of the
determinations of phenomena (existing, as they do, apart from each
other, and yet contemporaneously), is requisite to justify us in
saying that the reciprocal succession of perceptions has its
foundation in the object, and to enable us to represent coexistence as
objective. But that relation of substances in which the one contains
determinations the ground of which is in the other substance, is the
relation of influence. And, when this influence is reciprocal, it is
the relation of community or reciprocity. Consequently the coexistence
of substances in space cannot be cognized in experience otherwise
than
under the precondition of their reciprocal action. This is therefore
the condition of the possibility of things themselves as objects of
experience.
Things are coexistent, in so far as they exist in one and the same
time. But how can we know that they exist in one and the same time?
Only by observing that the order in the synthesis of apprehension of
the manifold is arbitrary and a matter of indifference, that is to
say, that it can proceed from A, through B, C, D, to E, or
contrariwise from E to A. For if they were successive in time (and
in the order, let us suppose, which begins with A), it is quite
impossible for the apprehension in perception to begin with E and go
backwards to A, inasmuch as A belongs to past time and, therefore,
cannot be an object of apprehension.
Let us assume that in a number of substances considered as phenomena
each is completely isolated, that is, that no one acts upon another.
Then I say that the coexistence of these cannot be an object of
possible perception and that the existence of one cannot, by any
mode of empirical synthesis, lead us to the existence of another.
For we imagine them in this case to be separated by a completely
void space, and thus perception, which proceeds from the one to the
other in time, would indeed determine their existence by means of a
following perception, but would be quite unable to distinguish whether
the one phenomenon follows objectively upon the first, or is
coexistent with it.
Besides the mere fact of existence, then, there must be something by
means of which A determines the position of B in time and, conversely,
B the position of A; because only under this condition can
substances be empirically represented as existing contemporaneously.
Now that alone determines the position of another thing in time
which is the cause of it or of its determinations. Consequently
every substance (inasmuch as it can have succession predicated of it
only in respect of its determinations) must contain the causality of
certain determinations in another substance, and at the same time
the effects of the causality of the other in itself. That is to say,
substances must stand (mediately or immediately) in dynamical
community with each other, if coexistence is to be cognized in any
possible experience. But, in regard to objects of experience, that
is absolutely necessary without which the
experience of these
objects would itself be impossible. Consequently it is absolutely
necessary that all substances in the world of phenomena, in so far
as they are coexistent, stand in a relation of complete community of
reciprocal action to each other.
The word community has in our language* two meanings, and contains
the two notions conveyed in the Latin communio and commercium. We
employ it in this place in the latter sense— that of a dynamical
community, without which even the community of place (communio spatii)
could not be empirically cognized. In our experiences it is easy to
observe that it is only the continuous influences in all parts of
space that can conduct our senses from one object to another; that the
light which plays between our eyes and the heavenly bodies produces
a mediating community between them and us, and thereby evidences their
coexistence with us; that we cannot empirically change our position
(perceive this change), unless the existence of matter throughout
the whole of space rendered possible the perception of the positions
we occupy; and that this perception can prove the contemporaneous
existence of these places only through their reciprocal influence, and
thereby also the coexistence of even the most remote objects— although
in this case the proof is only mediate. Without community, every
perception (of a phenomenon in space) is separated from every other
and isolated, and the chain of empirical representations, that is,
of experience, must, with the appearance of a new object, begin
entirely de novo, without the least connection with preceding
representations, and without standing towards these even in the
relation of time. My intention here is by no means to combat the
notion of empty space; for it may exist where our perceptions cannot
exist, inasmuch as they cannot reach thereto, and where, therefore, no
empirical perception of coexistence takes place. But in this case it
is not an object of possible experience.
The following remarks may be useful in the way of explanation. In
the mind, all phenomena, as contents of a possible experience, must
exist in community (communio) of apperception or consciousness, and in
so far as it is requisite that objects be represented as coexistent
and connected, in so far must they reciprocally determine the position
in time of each
other and thereby constitute a whole. If this
subjective community is to rest upon an objective basis, or to be
applied to substances as phenomena, the perception of one substance
must render possible the perception of another, and conversely. For
otherwise succession, which is always found in perceptions as
apprehensions, would be predicated of external objects, and their
representation of their coexistence be thus impossible. But this is
a reciprocal influence, that is to say, a real community
(commercium) of substances, without which therefore the empirical
relation of coexistence would be a notion beyond the reach of our
minds. By virtue of this commercium, phenomena, in so far as they
are apart from, and nevertheless in connection with each other,
constitute a
compositum reale. Such
composita are possible in many
different ways. The three dynamical relations then, from which all
others spring, are those of inherence, consequence, and composition.
These, then, are the three analogies of experience. They are nothing
more than principles of the determination of the existence of
phenomena in time, according to the three modi of this
determination; to wit, the relation to time itself as a quantity
(the quantity of existence, that is, duration), the relation in time
as a series or succession, finally, the relation in time as the
complex of all existence (simultaneity). This unity of determination
in regard to time is thoroughly dynamical; that is to say, time is not
considered as that in which experience determines immediately to every
existence its position; for this is impossible, inasmuch as absolute
time is not an object of perception, by means of which phenomena can
be connected with each other. On the contrary, the rule of the
understanding, through which alone the existence of phenomena can
receive synthetical unity as regards relations of time, determines for
every phenomenon its position in time, and consequently a priori,
and with validity for all and every time.
By nature, in the empirical sense of the word, we understand the
totality of phenomena connected, in respect of their existence,
according to necessary rules, that is, laws. There are therefore
certain laws (which are moreover a priori) which
make nature possible;
and all empirical laws can exist only by means of experience, and by
virtue of those primitive laws through which experience itself becomes
possible. The purpose of the analogies is therefore to represent to us
the unity of nature in the connection of all phenomena under certain
exponents, the only business of which is to express the relation of
time (in so far as it contains all existence in itself) to the unity
of apperception, which can exist in synthesis only according to rules.
The combined expression of all is this: "All phenomena exist in one
nature, and must so exist, inasmuch as without this
a priori unity, no
unity of experience, and consequently no determination of objects in
experience, is possible."
As regards the mode of proof which we have employed in treating of
these transcendental laws of nature, and the peculiar character of
we must make one remark, which will at the same time be important as a
guide in every other attempt to demonstrate the truth of
intellectual and likewise synthetical propositions a priori. Had we
endeavoured to prove these analogies dogmatically, that is, from
conceptions; that is to say, had we employed this method in attempting
to show that everything which exists, exists only in that which is
permanent— that every thing or event presupposes the existence of
something in a preceding state, upon which it follows in conformity
with a rule— lastly, that in the manifold, which is coexistent, the
states coexist in connection with each other according to a rule—
all our labour would have been utterly in vain. For more conceptions
of things, analyse them as we may, cannot enable us to conclude from
the existence of one object to the existence of another. What other
course was left for us to pursue? This only, to demonstrate the
possibility of experience as a cognition in which at last all
objects must be capable of being presented to us, if the
representation of them is to possess any objective reality. Now in
this third, this mediating term, the essential form of which
consists in the synthetical unity of the apperception of all
phenomena, we found a priori conditions of the universal and necessary
determination as to time of all existences in the world of
phenomena, without which the empirical determination thereof as to
time would itself be impossible, and we also discovered rules of
synthetical unity a priori, by means of which we could
anticipate
experience. For want of this method, and from the fancy that it was
possible to discover a dogmatical proof of the synthetical
propositions which are requisite in the empirical employment of the
understanding, has it happened that a proof of the principle of
sufficient reason has been so often attempted, and always in vain. The
other two analogies nobody has ever thought of, although they have
always been silently employed by the mind,
* because the guiding thread
furnished by the categories was wanting, the guide which alone can
enable us to discover every hiatus, both in the system of
conceptions and of principles.
[*]
The unity of the universe, in which all phenomena to be
connected, is evidently a mere consequence of the admitted principle
of the community of all substances which are coexistent. For were
substances isolated, they could not as parts constitute a whole, and
were their connection (reciprocal action of the manifold) not
necessary from the very fact of coexistence, we could not conclude
from the fact of the latter as a merely ideal relation to the former
as a real one. We have, however, shown in its place that community
is the proper ground of the possibility of an empirical cognition of
coexistence, and that we may therefore properly reason from the latter
to the former as its condition.