Critical of the pure reason

First section: space

Metaphysical exposure of the concept of space

• 1) space is not for Kant a concept drawn from the experiment. It is always already there, and constitutes the base of any possible external experiment. It would be impossible differently to represent an object out of us (for example, while going, the street that one comes to leave) or to differentiate an object from another (without space, the objects could not be located).
• 2) space is thus a " necessary representation a priori which is used as base with all the intuitions extérieures". One can imagine an empty space, deprived of objects. But one cannot not represent space. This is why, explains Kant, it does not have there dependence of space compared to the objects, but well rather dependence of the objects compared to the space which constitutes their base and conditions their possibility.
• 3) (this point was removed in the version of 1787) It is because, continues Kant, of the character necessary and a priori of space that the principles a priori of the geometry are true in an indisputable way (i.e. at the same time universal and necessary) and can be built a priori . If space did not have this statute of necessary representation a priori , then all these principles, as that which wants that by two points can pass only one line, would not be universal any more and necessary but would have on the contrary the relativity of the induction and the " contingency of the perception". That space does not have that three dimensions would not be any more one indisputable principle of the geometry according to Kant, and one should be satisfied to say " that one did not find of space which had more than three dimensions".
• 4) space is a pure intuition, not a concept developed by means of a speech. The proof in is, for Kant, which it is impossible to differently represent space than like single. One can certainly separate space in various parts, but those could be thought only in him. In the same way, the geometrical principles are not deduced from general concepts like that of right-hand side, but only of the intuition.
• 5) space is an infinite size. Space, because it is able to contain an infinite quantity of representation, is well an intuition and not a concept.

Exposure transcendantale of the concept of space

Kant will start from a report, that of the existence of the geometry like science allowing of the summary knowledges a priori , to try to define space. For him, space must be an intuition because the proposals of the Euclidean geometry are indisputable. It reasons so to speak ``ab actu AD poses'': if that exists, that must be understandable. Because synthetic judgments a priori are possible, space is an intuition (and not, again, a concept, because one can draw from a concept no proposal which exceeds it, no synthetic judgment). Moreover, this intuition must be in us way a priori . It is thus about an originating intuition, in us before any perception of an object, whatever he is. It thus has its seat in the subject itself: it is, known as Kant, " the formal property which has the subject to be affected by objets". Contrary to the understanding, space is not an element of the spirit which it applies to the experiment, but well rather the form according to which it is originally opened with the significant experiment. Space is not a concept, a construction of the spirit, but the mode even according to which the objects appear to us: a pure intuition presents in us originally.

Consequences of the preceding concepts

Second section: time

Metaphysical exposure of the concept of time

• 1) As space, time " is not an empirical concept which derives from a expérience". It is always already there, upstream of the experiment.
• 2) times, if it is following the example space a representation necessary, serves to him " of base to all intuitions" (not only with the interior intuitions, therefore). " In him seul" , insists Kant, " any reality of the phénomènes" is possible;. Time is thus the condition of any intuition, even space. This prevalence of time on space is essential.
• 3) As it is a necessary representation a priori , time makes possible the principles universally and necessarily truths of the geometry.
• 4) times is a " pure form of the intuition" , not a " concept discursif". Otherwise, no summary knowledge a priori (Kant takes the example of impossibility here that different times are simultaneous) would be possible.
• 5) " Any given size of time is not possible that by the limitations of a single time which is used to him as fondement". To speak about parts of time is not possible that by limiting a single, infinite time at the origin.

Exposure transcendantale of the concept of time

Exposure Transcendantal E

Kant undertakes to show that sciences (mathematics and physics) would be impossible if space and time, like forms a priori , were not the transcendantaux bases. “Take, for example, this proposal: Two straight lines cannot contain any space nor, consequently, to form of figure; and seek to derive this proposal from the concept of straight line and that of the number two”. Only space, as a pure form a priori of the sensitivity, gives possible such a synthetic judgment, which will be consequently a priori. If the geometry did not make use of this pure intuition a priori, it would be empirical, it would be an applied science. The geometry does not proceed by measurements but by demonstrations. Kant makes rest its demonstration of the apriority of space on the exemplary success of the geometry. If his argument is tackled, one would then call into question the universality of the geometry. In addition, time will be the pure intuition a priori which will make possible mathematics. Time is not either a concept, if not he would obey the requirements of formal logic (thus with the principle of non-contradiction). However, time makes it possible to derogate from the principle of non-contradiction: indeed, it is possible to say that has and non-A is in the same place if one considers them in different times. Time and space cannot thus be regarded as existing beings in oneself. They are the forms a priori of the sensory intuition. Nothing never meets in an experiment which is not inscribable in a time and a place.

At the end of this chapter one finds a warning of Kant releasing it from any subjective idealism: “When I say that, in space and time, as well the intuition of the external objects as the intuition of the spirit by itself represent each one their object as it affects our directions, i.e. as it appears to us, I do not want to say that these objects are a simple appearance”. Kant does nothing but distinguish the phenomenon of the object. He does not declare that nothing exists apart from itself or of its own conscience, far from there. He in addition makes of it an explicit refutation in the section: paralogism of the ideality of the external report/ratio. To be distinguished from this subjective idealism, denying the existence of the outside world, it defines its position as an idealism transcendantal* granted with an empirical realism: “Our explanations thus teach us reality (i.e. the value objectifies) space from time and at the same time the ideality of space from time compared to the things, when they are considered in themselves We thus affirm the empirical reality of space, though we affirm of it at the same time the ideality transcendantale”.

Analytical transcendantale

Analytical the transcendantale is the second great moment of the theory of the elements. It is fundamental because it contains on the one hand celebrates it transcendantale deduction categories and moreover the solution with the question which underlies all Criticism: " how are the synthetic judgments possible a priori "?

Just like esthetics transcendantale it contains a metaphysical exposure as well as a transcendantale deduction.

Deliver I: Analytical of the concepts

Exposure of the pure concepts of the understanding

The analytical one of the Concept S draws initially the picture of the categories or concepts of the pure Entendement. They are for Kant the twelve concepts a priori which are the base of all Connaissance scientific. This list is moreover, with the eyes of Kant, exhaustive.

But to obtain this table, known as Kant, it is necessary to have a directing wire. It is in the table of the judgments that it finds it:

Deduction of the pure concepts of the understanding

But Kant wants moreover to show that these various categories are the base Transcendantal of any knowledge.

Kant is confronted here with the thorny question of the legitimacy of the use of the categories. The problem is the following: the categories are Concept S.A. priori - how in this case knowledge if there is the right to apply them to the Phénomène S known by the Expérience. Because, first of all, it seems well that one can know the empirical Phénomène S without making use of Concept S independent of the Expérience. Apparently, a Physicien does not need to have Concept S.A. priori to know the Nature.

Kant will thus be given for task, during the Déduction Transcendantal E of the categories, to determine if the use of the categories is legitimate to know the Phénomène S known by the Expérience and so yes up to what point.

It evokes three possibilities to explain why Concept S can be applied to the Expérience:

• Is these concepts derives from the Expérience or more exactly is the result of a process of induction. However, this cannot be true categories because they are a priori and thus independent of the experiment.
• Or then the concepts a priori can be applied to the Phénomène S empirical thanks to a harmony preestablished as at Leibniz. This possibility is not either bearable with the eyes of Kant.
• Or it should be affirmed that the Concept S.A. priori are themselves the base of the Expérience. This solution with the advantage of solving in an indisputable way the question of the legitimacy of the application of the categories to the Experiment. It is this answer which Kant will defend.

Deliver II: Analytical of the principles

Kant works out a system here either Concept S but of the principles of the Entendement. The principles are rules that the Entendement gives itself to itself in way a priori and who govern our Expérience Phénomène S. There are four types of principles, each one maintaining a bond with the four main categories of the Entendement:

• Principle of the axioms of the Intuition; in relation to the concept of quantity.

• Principle of anticipations of the Perception; dependant on quality.

• Principle of the analogies of the Experiment; dependant on the relation.

• Postulates of the Thought empirical in general: dependant on method.

The second division: dialectical the transcendantale

Dialectical the transcendantale is the third great moment of the “criticism of the pure reason” after esthetics and analytical the transcendantales. Kant studies there the illegitimate operation of the Entendement; it works out a theory of the errors and illusions of the Entendement. It is necessary to distinguish well between the dialectical logic, which are interested in the errors of Raisonnement S in their character formal and disregarded the Connaissance itself, and dialectical the transcendantale, which is interested in the errors of the reason as it leaves the limits the experiment. The dialectical transcendantale tries to distinguish between what concerns the nouménal and the phenomenal , and by operating this division, it cures the evil which corrodes the Raison at the same time as it discovers it. Indeed, to distinguish between nouménal and phenomenal prevents to a certain extent to make an illegitimate exercise of the reason. However these illusions, because they are related to the nature even of the human reason, return constantly and are impossible to dissipate. These illusions of the pure reason are the Paralogisme S, the Antinomie S and the Ideal of the reason.

The introduction

The introduction has as a function to explain the function of the reason (" Vernunft") for the constitution of pseudo-knowledge metaphysics: dialectical the transcendantale thus brings the answer to the question that Kant posed in the introduction: " how metaphysics is possible like natural tendency? ".

It is initially necessary to differentiate the reason from faculty to judge (" Urteilskraft") who allows to subsume a particular object under a predicate. A “object” being very concept or nobody to which one can allot a quality (or predicate). If for example I say: “Socrate is mortal” I subsume a concept (Socrate) under a predicate (“mortal”). The reason also makes it possible it to subsume a concept under a predicate. Only it does it in another way that faculty to judge. If I say for example:

• “Socrate is a man”
• But the men are mortals”
• Donc Socrate is mortal”, I subsume an object (Socrate) under a predicate (mortal). But this preaching is not done directly: one subsumes a first proposal (“Socrate is a man”) under a more general proposal (“the men are mortals”) by means of a third intermediate term (here: “man”).

The reason is thus anything else for Kant only faculty to subsume a particular proposal under a more general proposal through an average concept. It is besides the great difference between the reason and faculty to judge because the last subsumes without passing by an intermediate term.

Kant tries to define by there the function of the reason. But in what is the reason the source of metaphysics? It is that the reason tends to unceasingly subsume knowledge under general rules (or “principles” as known as Kant) until it arrives at a principle which is not let any more subsume under a more general principle. While trying to unify by principles the conditioned knowledge (by the experiment) of the understanding it will make a movement on the basis of principles immanents to go towards transcendent principles i.e. exceeding the limits of the experiment. The reason by its nature even tends towards a knowledge “inconditionnée”, towards “inconditionné” (“das Unbedingte”). However, it leaves by there the field of the experiment of which it does not hold any more account. She seeks an “absolute” principle consequently.

Kant explains then how the reason arrives at the various concepts metaphysics. To simplify one can say that the reason will seek these three following inconditionnées proposals:

• a inconditionnée substance (it will be the heart: cf criticizes rational psychology);
• a inconditionnée continuation (i.e which will not be limited) conditions (it will be inter alia freedom: cf the criticism of rational cosmology);
• an entity having in a inconditionnée way (i.e without restriction) all the possible predicates (it will be God: cf rational theology).

Paralogisms

The Paralogisme S are Raisonnement S fallacious of rational psychology concerning the nature of the heart.

Rational psychology is at the base one of the three branches of metaphysics such as had defined Wolf in its philosophical system. It is about the discipline which analyzes the properties of the heart a priori i.e. without resorting to the experiment. This is all the more clear when one remembers that the fundamental goal of this discipline is to prove the immortality of the heart, proof which can be only a priori . One should not thus confuse rational psychology with the psychology heard like empirical study of human psychism.

The importance of the criticism of rational psychology is due to the fact that she claims to know her object (the heart) by a nonsignificant intuition more exactly by a simple introspection. This thesis is fundamental because it constitutes a challenge with the Kantian position according to which an intuition can be only sensitive. It is even on this idea that the resolution of the question rests “how are possible the synthetic judgments a priori ” in the Analytical one. The refutation of rational psychology is thus to some extent a defense of one of the bases of the Kantian thought.

Discrepancies

Stakes

This passage of the Critique of the pure reason has a very particular significance because internal and insoluble contradictions of the first two discrepancies constitute for Kant the proof of the validity of the revolution copernician while the resolution of the question “how are possible the synthetic judgments a priori ” constitutes the positive response of it.

The Discrepancies are important for another reason. Kant calls upon an extremely original process of resolution of contradictions resting on the distinction between phenomena and noumenes and which leads it to exceed some of the oldest quarrels of metaphysics. Kant will try to solve the discrepancies while proceeding to a going beyond; he explains why each opposite thesis are true but each time according to from the different points of view. Those of metaphysical dogmatism are true from the point of view of noumenes, those of empiricism are it on the plan of the phenomena. Kant tries here to carry out peace between empiricism and dogmatism.

Finally the third discrepancy revêt an essential significance because it will allow the development of moral philosophy in the Critique of the reason practices.

Exposure of the four discrepancies

The first discrepancy relates to the finitude or not of the world.

• the world has a beginning in time and is not limited from a space point of view.

• the world does not have a beginning and does not have limits in space and it is infinite as well from the point of view of the time as of space.

The second door on the existence or not of an indivisible simple entity.

• Any substance made up consists of simple parts and there does not exist something of other nowhere but the simple one or that what of it is made up.

• No thing made up in the world consists of simple parts and there nowhere exists nothing simple in him.

The resolution of the first and the second discrepancy are identical. In their two cases Kant will show that it are contradictory i.e. they are excluded mutually. However, it will use this fact as starting point of a negative evidence (or more exactly by the absurdity) of the validity of the revolution copernician. The first and the second discrepancy leave the principle which the things are recognizable in themselves and not only according to the executives a priori of our experiment (cf Esthétique transcendantale). But this pleasing thesis with contradictions indépassables as the first two discrepancies show it. The thesis according to which the objects can be known in themselves is thus intolerable.

The third relates to the existence or not freedom.

• causality according to the natural laws is not the only form of causality from which one can deduce the unit from the phenomena of the world. It is necessary to suppose moreover a causality by freedom to explain the phenomena.

• There does not exist freedom: all in the world takes place according to the natural laws.

The fourth refers to the existence or not of God.

• a being necessary in manner inconditionné forms part of the world that it is like its part or as its cause.

• There nowhere exists a being necessary in manner inconditionné that it is in the world or apart from the world or as its cause.

The resolution of the third and the fourth discrepancy are they also identical. Kant explains why the thesis and the antithesis of these two discrepancies are contrary (and noncontradictory with the difference in the first two discrepancies). It is possible according to Kant to affirm all at the same time the thesis and the antithesis. Only it will be necessary to be placed from the different point of view. The thesis will be true from a nouménal point of view, i.e. if one considers the things in themselves, by disregarding form a priori of the sensitivity. The concept of freedom and a being of which absolutely necessary (God actually) will be thus concepts to which one cannot allot any empirical reality (Kant speaks about Ideas to indicate this type of precise concept). One does not observe God or freedom as an empirical phenomenon is observed. It is obvious that such concepts will be without utility for the scientific knowledge. The antithesis on the other hand will be true from a phenomenal point of view i.e. if one considers the objects such as they given to us in the experiment. The antithesis will be true within the framework of physical sciences.

The Ideal of the pure reason

In this section, Kant refutes in a systematic way all the possible evidence of the existence of God. Those, says it, can be brought back to three:

1. ontological proof;
2. cosmological proof;
3. physicotheological proof.

The three evidence of the existence of God

Ontological proof

The ontological proof is based on the only concept of God to deduce the existence from it. The argumentation is the following one:

1. something of necessary cannot not exist (if not it would be contingent);
2. gold God is a being necessary (it is a property included/understood in its concept);
3. thus God exists.

Cosmological proof

The cosmological proof is that which rests, not on the only concept of God, but on the existence of the world. One can formulate it in the following way:

1. All that has a cause;
2. but there exists a world, which cannot be the cause of itself;
3. thus it must have due a being which either causes itself (God).

Physicotheological proof

The physicotheological proof rests on the observation of the final causes:

1. all that contains ends is the work of an intelligence;
2. but the world contains ends: organized beings, beauty of nature, makes that the products of nature are intended for the man;
3. thus there exists an intelligence higher at the origin of the world.

Reduction of all the evidence to the ontological argument

Kant, after having listened to the last Gorgoroth, exposes these three arguments, and shows that they are reduced all to the first (ontological argument ).

After having observed the contingency of the world, the cosmological argument must pose the existence of a being necessary; it is then obliged to resort to the ontological argument , which deduces from the concept of God that there exists.

As for the physicotheological argument , starting from the observation of ends in nature, concludes from it that it was necessary a creator so that the world exists (cosmological argument ), and that this creator must necessarily exist (ontological argument ).

Refutation of the ontological argument

By refuting the ontological argument, Kant thus intends to refute all the possible evidence of the existence of God. Its argumentation thus will consist in establishing that the existence of God cannot be deduced from sound only concept.

“To be is not a real predicate”, affirms Kant. By real predicate, it is necessary to hear “predicate of the thing” ( LMBO ). The existence is not a property of the same things, which can belong or not to their concept, but the method of a judgment.

Kant gives the example of 100 Thaler S. 100 thalers possible are not worth than 100 thalers more real. Admittedly, one is richer if there are 100 thalers real that 100 possible thalers, but it is because, actually, there is 0 thaler, and that 0 are lower than 100. In themselves, 100 possible thalers and 100 thalers real have the same value exactly.

The fact that the 100 thalers real exist does not add anything to their concept : their concept does not receive an additional property; the existence is not a property which is integrated into the concept, it is a certain relationship between the judgment, the concept and the phenomenon.

Consequently, one cannot legitimately say that the existence belongs to the concept of God: it is to confuse the conceptual contents and the existential predicate of a thing. The ontological argument is thus invalid; and in its fall it involves all the other arguments, which are reducible there in last authority.

Theory transcendantale of the method

Discipline pure reason

Canon of the pure reason

“The opinion is a credit (Fürwahrhalten) conscious of being insufficient subjectively very as much as objectively. If the credit is sufficient only subjectively and at the same time is held for objectively insufficient, it is called belief. Lastly, the credit which is sufficient as well subjectively as objectively calls the knowledge. Subjective sufficiency is called conviction (for myself), objective sufficiency is called certainty (for each one). I will not stop clarifying concepts also easily comprehensible. ” Kant

The architectonic one of the pure reason

History of the pure reason