Critique of Pure Reason

by Immanuel Kant

  Permanence, therefore, is a necessary condition under which alone phenomena, as things or objects, can be determined in a possible experience. What the empirical criterion of this necessary permanence, or of the substantiality of phenomena may be, we shall have to explain in the sequel.

  B

  [Second Analogy

  Principle of Production12

  Everything that happens (begins to be), presupposes something on which it follows according to a rule]

  Proof

  The apprehension of the manifold of phenomena is always successive. The representations of the parts follow one upon another. Whether they also follow one upon the other in the object is a second point for reflection, not contained in the former. We may indeed call everything, even every representation, so far as we are conscious of it, an object; but it requires a more profound investigation to discover what this word may mean with regard to phenomena, not in so far as they (as representations) are objects, but in so far as they only signify an object. So far as they, as representations only, are at the same time objects of consciousness, they cannot be distinguished from our apprehension, that is from their being received in the synthesis of our imagination, and we must therefore say, that the manifold of phenomena is always produced in the mind successively. If phenomena were things by themselves, the succession of the representations of their manifold would never enable us to judge how that manifold is connected in the object. We have always to deal with our representations only; how things may be by themselves (without reference to the representations by which they affect us) is completely beyond the sphere of our knowledge. Since, therefore, phenomena are not things by themselves, and are yet the only thing that can be given to us to know, I am asked to say what kind of connection in time belongs to the manifold of the phenomena itself, when the representation of it in our apprehension is always successive. Thus, for instance, the apprehension of the manifold in the phenomenal appearance of a house that stands before me, is successive. The question then arises, whether the manifold of the house itself be successive by itself, which of course no one would admit. Whenever I ask for the transcendental meaning of my concepts of an object, I find that a house is not a thing by itself, but a phenomenon only, that is, a representation the transcendental object of which is unknown. What then can be the meaning of the question, how the manifold in the phenomenon itself (which is not a thing by itself) may be connected? Here that which is contained in our successive apprehension is considered as representation, and the given phenomenon, though it is nothing but the whole of those representations, as their object, with which my concept, drawn from the representations of my apprehension, is to accord. As the accord between knowledge and its object is truth, it is easily seen, that we can ask here only for the formal conditions of empirical truth, and that the phenomenon, in contradistinction to the representations of our apprehension, can only be represented as the object different from them, if it is subject to a rule distinguishing it from every other apprehension, and necessitating a certain kind of conjunction of the manifold. That which in the phenomenon contains the condition of this necessary rule of apprehension is the object.

  Let us now proceed to our task. That something takes place, that is, that something, or some state, which did not exist before, begins to exist, cannot be perceived empirically, unless there exists antecedently a phenomenon which does not contain that state; for a reality, following on empty time, that is a beginning of existence, preceded by no state of things, can be apprehended as little as empty time itself. Every apprehension of an event is therefore a perception following on another perception. But as this applies to all synthesis of apprehension, as I showed before in the phenomenal appearance of a house, that apprehension would not thereby be different from any other. But I observe at the same time, that if in a phenomenon which contains an event I call the antecedent state of perception A, and the subsequent B, B can only follow A in my apprehension, while the perception A can never follow B, but can only precede it. I see, for instance, a ship gliding down a stream. My perception of its place below follows my perception of its place higher up in the course of the stream, and it is impossible in the apprehension of this phenomenon that the ship should be perceived first below and then higher up. We see therefore that the order in the succession of perceptions in our apprehension is here determined, and our apprehension regulated by that order. In the former example of a house my perceptions could begin in the apprehension at the roof and end in the basement, or begin below and end above: they could apprehend the manifold of the empirical intuition from right to left or from left to right. There was therefore no determined order in the succession of these perceptions, determining the point where I had to begin in apprehension, in order to connect the manifold empirically; while in the apprehension of an event there is always a rule, which makes the order of the successive perceptions (in the apprehension of this phenomenon) necessary.

  In our case, therefore, we shall have to derive the subjective succession in our apprehension from the objective succession of the phenomena, because otherwise the former would be entirely undetermined, and unable to distinguish one phenomenon from another. The former alone proves nothing as to the connection of the manifold in the object, because it is quite arbitrary. The latter must therefore consist in the order of the manifold in a phenomenon, according to which the apprehension of what is happening follows upon the apprehension of what has happened, in conformity with a rule. Thus only can I be justified in saying, not only of my apprehension, but of the phenomenon itself, that there exists in it a succession, which is the same as to say that I cannot arrange the apprehension otherwise than in that very succession.

  In conformity with this, there must exist in that which always precedes an event the condition of a rule, by which this event follows at all times, and necessarily; but I cannot go back from the event and determine by apprehension that which precedes. For no phenomenon goes back from the succeeding to the preceding point of time, though it is related to some preceding point of time, while the progress from a given time to a determined following time is necessary. Therefore, as there certainly is something that follows, I must necessarily refer it to something else which precedes, and upon which it follows by rule, that is, by necessity. So that the event, as being conditional, affords a safe indication of some kind of condition, while that condition itself determines the event.

  If we supposed that nothing precedes an event upon which such event must follow according to rule, all succession of perception would then exist in apprehension only, that is, subjectively; but it would not thereby be determined objectively, what ought properly to be the antecedent and what the subsequent in perception. We should thus have a mere play of representations unconnected with any object, that is, no phenomenon would, by our perception, be distinguished in time from any other phenomenon, because the succession in apprehension would always be uniform, and there would be nothing in the phenomena to determine the succession, so as to render a certain sequence objectively necessary. I could not say therefore that two states follow each other in a phenomenon, but only that one apprehension follows another, which is purely subjective, and does not determine any object, and cannot be considered therefore as knowledge of anything (even of something purely phenomenal).

  If therefore experience teaches us that something happens, we always presuppose that something precedes on which it follows by rule. Otherwise I could not say of the object that it followed, because its following in my apprehension only, without being determined by rule in reference to what precedes, would not justify us in admitting an objective following.13 It is therefore always with reference to a rule by which phenomena as they follow, that is as they happen, are determined by an antecedent state, that I can give an objective character to my subjective synthesis (of apprehension); nay, it is under this supposition only that an experience of anything that hap pens becomes possible.

  It might seem indeed as if this were in contradic
tion to all that has always been said on the progress of the human understanding, it having been supposed that only by a perception and comparison of many events, following in the same manner on preceding phenomena, we were led to the discovery of a rule according to which certain events always follow on certain phenomena, and that thus only we were enabled to form to ourselves the concept of a cause. If this were so, that concept would be empirical only, and the rule which it supplies, that everything which happens must have a cause, would be as accidental as experience itself. The universality and necessity of that rule would then be fictitious only, and devoid of any true and general validity, because not being a priori, but founded on induction only. The case is the same as with other pure representations a priori (for instance space and time), which we are only able to draw out as pure concepts from experience, because we have put them first into experience, nay, have rendered experience possible only by them. It is true, no doubt, that the logical clearness of this representation of a rule, determining the succession of events, as a concept of cause, becomes possible only when we have used it in experience, but, as the condition of the synthetical unity of phenomena in time, it was nevertheless the foundation of all experience, and consequently preceded it a priori.

  It is necessary therefore to show by examples that we never, even in experience, ascribe the sequence or consequence (of an event or something happening that did not exist before) to the object, and distinguish it from the subjective sequence of our apprehension, except when there is a rule which forces us to observe a certain order of perceptions, and no other; nay, that it is this force which from the first renders the representation of a succession in the object possible.

  We have representations within us, and can become conscious of them; but however far that consciousness may extend, and however accurate and minute it may be, yet the representations are always representations only, that is, internal determinations of our mind in this or that relation of time. What right have we then to add to these representations an object, or to ascribe to these modifications, beyond their subjective reality, another objective one? Their objective character cannot consist in their relation to another representation (of that which one wished to predicate of the object), for thus the question would only arise again, how that representation could again go beyond itself, and receive an objective character in addition to the subjective one, which belongs to it, as a determination of our mind. If we try to find out what new quality or dignity is imparted to our representations by their relation to an object, we find that it consists in nothing but the rendering necessary the connection of representations in a certain way, and subjecting them to a rule; and that on the other hand they receive their objective character only because a certain order is necessary in the time relations of our representations.

  In the synthesis of phenomena the manifold of our representations is always successive. No object can thus be represented, because through the succession which is common to all apprehensions, nothing can be distinguished from anything else. But as soon as I perceive or anticipate that there is in this succession a relation to an antecedent state from which the representation follows by rule, then something is represented as an event, or as something that happens: that is to say, I know an object to which I must assign a certain position in time, which, after the preceding state, cannot be different from what it is. If therefore I perceive that something happens, this representation involves that something preceded, because the phenomenon receives its position in time with reference to what preceded, that is, it exists after a time in which it did not exist. Its definite position in time can only be assigned to it, if in the antecedent state something is presupposed on which it always follows by rule. It thus follows that, first of all, I cannot invert the order, and place that which happens before that on which it follows; secondly, that whenever the antecedent state is there, the other event must follow inevitably and necessarily. Thus it happens that there arises an order among our representations, in which the present state (as having come to be), points to an antecedent state, as a correlative of the event that is given; a correlative which, though as yet indefinite, refers as determining to the event, as its result, and connects that event with itself by necessity, in the succession of time.

  If then it is a necessary law of our sensibility, and therefore a formal condition of all perception, that a preceding necessarily determines a succeeding time (because I cannot arrive at the succeeding time except through the preceding), it is also an indispensable law of the empirical representation of the series of time that the phenomena of past time determine every existence in succeeding times, nay, that these, as events, cannot take place except so far as the former determine their existence in time, that is, determine it by rule. For it is of course in phenomena only that we can know empirically this continuity in the coherence of times.

  What is required for all experience and renders it possible is the understanding, and the first that is added by it is not that it renders the representation of objects clear, but that it really renders the representation of any object for the first time possible. This takes place by the understanding transferring the order of time to the phenomena and their existence, and by assigning to each of them as to a consequence a certain a priori determined place in time, with reference to antecedent phenomena, without which place phenomena would not be in accord with time, which determines a priori their places to all its parts. This determination of place cannot be derived from the relation in which phenomena stand to absolute time (for that can never be an object of perception); but, on the contrary, phenomena must themselves determine to each other their places in time, and render them necessary in the series of time. In other words, what happens or follows must follow according to a general rule on that which was contained in a previous state. We thus get a series of phenomena which, by means of the understanding, produces and makes necessary in the series of possible perceptions the same order and continuous coherence which exists a priori in the form of internal intuition (time), in which all perceptions must have their place.

  That something happens is therefore a perception which belongs to a possible experience, and this experience becomes real when I consider the phenomenon as determined with regard to its place in time, that is to say, as an object which can always be found, according to a rule, in the connection of perceptions. This rule, by which we determine everything according to the succession of time, is this: the condition under which an event follows at all times (necessarily) is to be found in what precedes. All possible experience therefore, that is, all objective knowledge of phenomena with regard to their relation in the succession of time, depends on 'the principle of sufficient reason.'

  The proof of this principle rests entirely on the following considerations. All empirical knowledge requires synthesis of the manifold by imagination, which is always successive, one representation following upon the other. That succession, however, in the imagination is not at all determined with regard to the order in which something precedes and something follows, and the series of successive representations may be taken as retrogressive as well as progressive. If that synthesis, however, is a synthesis of apperception (of the manifold in a given phenomenon), then the order is determined in the object, or, to speak more accurately, there is then in it an order of successive synthesis which determines the object, and according to which something must necessarily precede, and, when it is once there, something else must necessarily follow. If therefore my perception is to contain the knowledge of an event, or something that really happens, it must consist of an empirical judgment, by which the succession is supposed to be determined, so that the event presupposes another phenomenon in time on which it follows necessarily and according to a rule. If it were different, if the antecedent phenomenon were there, and the event did not follow on it necessarily, it would become to me a mere play of my subjective imaginations, or if I thought it to be objective, I should call it a dream. It is therefore the relation of ph
enomena (as possible perceptions) according to which the existence of the subsequent (what happens) is determined in time by something antecedent necessarily and by rule, or, in other words, the relation of cause and effect, which forms the condition of the objective validity of our empirical judgments with regard to the series of perceptions, and therefore also the condition of the empirical truth of them, and of experience. The principle of the causal relation in the succession of phenomena is valid therefore for all objects of experience, also (under the conditions of succession), because that principle is itself the ground of the possibility of such experience.

  Here, however, we meet with a difficulty that must first be removed. The principle of the causal connection of phenomena is restricted in our formula to their succession, while in practice we find that it applies also to their coexistence, because cause and effect may exist at the same time. There may be, for instance, inside a room heat which is not found in the open air. If I look for its cause, I find a heated stove. But that stove, as cause, exists at the same time with its effect, the heat of the room, and there is therefore no succession in time between cause and effect, but they are coexistent, and yet the law applies. The fact is, that the greater portion of the active causes14 in nature is coexistent with its effects, and the succession of these effects in time is due only to this, that a cause cannot produce its whole effect in one moment. But at the moment in which an effect first arises it is always coexistent with the causality of its cause, because if that had ceased one moment before, the effect would never have happened. Here we must well consider that what is thought of is the order, not the lapse of time, and that the relation remains, even if no time had lapsed. The time between the causality of the cause and its immediate effect can be vanishing (they may be simultaneous), but the relation of the one to the other remains for all that determinable in time. If I look upon a ball that rests on a soft cushion, and makes a depression in it, as a cause, it is simultaneous with its effect. But I nevertheless distinguish the two through the temporal relation of dynamical connection. For if I place the ball on a cushion, its smooth surface is followed by a depression, while, if there is a depression in the cushion (I know not whence), a leaden ball does by no means follow from it.