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 bees easy enough； although by the
mon 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 parison。 Besides； by this mode of induction we could
not attain to the pleteness 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
ing 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 （