Immanuel Kant

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In summary: Critique of Pure Reason, A533/B560)Kant maintained that synthetic a priori knowledge is not possible in the empirical realm, that is, knowledge that is based on experience. He claimed that all factual statements must be either analytic or synthetic (depending on whether the predicate of the judgement contains information that is not contained in the subject). However, he was careful to say that this is a priori judgement, not a fact.
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Chapter 8

Immanuel Kant (1724-1804)

EMPIRICISM, which commenced with postulates of confidence, after Hume seemed to end in barren scepticism which not only affronted common sense but made science impossible. The German philosopher Kant became very conscious of the fact that Hume had precipitated a crisis in philosophy. Against empirical thinking as he was, Kant, nevertheless, declared himself profoundly influenced by Hume, whom, he said; "First awoke me from my dogmatic slumbers."

Hume had argued that there could be no empirical base for the supposition of an objective existence of permanent "substances or of casuality". Our knowledge, we do possesses such knowledge is impossible if it merely comes from sensation. What if we have knowledge independent of sense experience: knowledge whose truth is certain even before experience - a priori knowledge? The truth that every event has a cause would be irrefutable and scientific analysis made possible.

A Priori Knowledge

A priori knowledge was for Kant the search for knowledge that is universal and necessary and independent of experience. "My question is", he wrote, "what we can hope to achieve with reason, when all the material and assistance of experience are taken away." (Preface to Critique of Pure Reason) and in this work itself:

"Experience is by no means the only field to which our understanding can be confined. Experience tells us what is, but not that is must be necessarily what it is and not otherwise. It therefore never gives us any really general truths; and our reason, which is particularly anxious for this class of knowledge, is roused by it rather than satisfied. General truths, which at the same time bear the character of an inward necessity, must be independent of experience - clear and certain in themselves."

Kant believed that the discovery of such knowledge was to be found in mathematics and nature (physics), such discovery being made possible through the structure of the mind. This, then, is the basic problem which the Critique sets out to solve.

The types of a priori knowledge, Kant claimed, fell into two groups; analytic and synthetic. The analytic consists of propositions or judgements where the truth can be determined without any reference to experience; solely on the basis of the terms employed. For example, "A red rose is red", and "all bodies are extended". These are universally true because what is predicated of the subject is already contained in the definition of the subject.

For synthetic a priori knowledge the predicate of the judgement must contain some information not contained in the subject. The judgement must be the result of a synthesis of these two separate notions, one being the subject about which the other, the predicate, asserts. Propositions which assert facts are synthetic when they describe an immediate experience such as, "This is black". But, having regard to Hume, Kant was careful to disregard factual statements which ventured beyond immediate experience. For example, "This piece of paper is white"... This is synthetic in that the predicate contains a concept not included in the subject. However, this is not a priori judgement, it is not universal nor independent from experience. It could be false that this paper is white and even if true, it does not have to be true at all times and places. Similarly a factual synthetic statement can be upset through the discovery of a new fact, like the statement: "All crows are black". It is possible to deny this proposition if we can produce a white crow. We cannot say that a white crow is unthinkable or a contradiction. We may say that it is unlikely: we cannot say that it is impossible. Truth or falsehood thus depends on correspondence with facts. A synthetic a priori judgement must contain some information not purely of a logical nature, nor dependent on empirical information for its truth since, according to Hume - that would always render it less than completely certain, universal or necessary.

Kant maintained that in mathematics and physics such universal judgement independent of experience were to be found. Such was the elementary proposition 7 + 5 = 12. This, he insisted, was a truth that was not merely true because of the definition of the terms involved, but because it contained more information in the predicate than was included in the bare concept '7' and '5'. In combining these two concepts into another which is their sum, a kind of intuition must take place, which introduces something new in the conclusion.

"That 5 should be added to 7 was no doubt implied in my concept of a sum 7 + 5, but not that the sum should be equal to 12. An arithmetical proposition is, therefore, always synthetical, which is seen more easily still by taking larger numbers, where we clearly perceive that, turn and twist our conceptions as we may, we could never by means of the mere analysis of our concepts and without the help of intuition arrive at the sum wanted."

Similarly, in geometrical truths, Kant claimed that one finds the same sort of synthetic element: for example, in the proposition, "A straight line is the shortest distance between two points. Here the concept "Straight line" does not include the notion of it being the shortest distance between two points and yet the statement is a necessary and universal truth. And in physics he contended, it is also the case that there are propositions like, "Every event has a cause," which are synthetic and also a priori.


The general problem confronting Kant was the question: "How are synthetic a priori judgements possible? His first answer is the claim that with every order or form of experience it takes the form of an a priori characteristic, which arises from the mind and not the outside world. Thus to Kant, the mind was not as it appeared to Locke and Hume, just "passive was", but active in organising, moulding and classifying perceptions it receives in the ordering of thought. The agent for selection of this ordering and classification of the material presented to it Kant claims to be the sense of space and the sense of time. The mind, in allocating its sensations in space and time attributes them to this object here or that object there. To this present time or to that past time. Space and time are not things perceived but or modes of perception - our tools for putting sense into sensation. Space and time are organs of perception. A priori, because all ordered experience involves and presupposes them. Without them sensations could never grow into perceptions. A priori, because it is inconceivable that we should ever have any future experience that will not involve them.


Besides the forms of intuition Kant believed that there must be principles or concepts for organising the general content of any possible experience in order to recognise it as a coherent proposition. Hume has shown that there were no necessary features in experience which could supply these factors, consequently says Kant, since we are capable of attaining organised and intelligible information about the world, we must have within ourselves the organising principles. Our minds structure and interpret the observations of our senses. Further, there must be a general conceptual scheme by which the types of items that we are acquainted with are ordered and related. These are what Kant calls the categories which he lists into four groups of three, involving such notions as causality, substance, accident, possibility etc. With the categories Kant claimed he had selected those basic ideas that are indispensable to thought and common to all mankind. When we think of the bewildering large number of words we use it seems almost impossible to select just those basic ideas that are indispensable to thought. Kant's solution is ingenious but out of fashion today. Modern physics dispenses with some of the categories. It can manage without causation and instead of space and time, Relativity employs intervals. The categories may be necessities at a certain level of thinking; but all of them are not essential in the most advanced field of science.

To summarise; We note sensation as being unorganised stimulus; perception as sensation organised; conception as organised perception, each a greater degree of order, sequence and unity. "Perceptions without conceptions", says Kant, "are blind!" If perceptions (sensations) wove themselves automatically into ordered thought, if mind were not an active effort hammering out order from chaos, how could the same sense experience leave one man mediocre, and another clever? Thus Kant claimed that he had made objects conform to the mind, whereas previous philosophers had made mind conform to objects.

[to be continued]
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Immanuel Kant [part 2]


The world then has order; but not of itself, but because the thought that knows the world through the ordering of the mind is the first stage in the classification of experience which has made science possible. Nevertheless, this knowledge is limited strictly to the field of actual experience. For Kant's analysis to be correct the world is a finished product to which the mind has contributed by its moulding forms. The object as it appears to us then, is a phenomenon, an appearance no doubt, very different from the external object before it came within reach of our senses. What the original object was we can never know. Kant calls it the "thing-in-itself" a noumenon (an unknown and unknownable substance or thing as it is in itself). It cannot be experienced, for in being experienced it would be changed by its passage through the ordering process of the mind. "It remains completely unknown to us what objects may be by themselves and apart from the receptivity of our senses. We know nothing but our manner of perceiving them; that manner being peculiar to us, and not necessarily shared by every being, though, no doubt, by every human being." (Critique of Pure Reason).

What then, of God, the immortality of the soul, or the freedom of the will, all of which have a prominent place in our system? Science is naive, it supposes it is dealing with things-in-themselves. Once it goes beyond the realm of experience it forgets its limitations and ends up with antinomies - propositions of which the opposite is neither more nor less acceptable. For example, there are excellent logical proofs that the world began in time and is limited in space. But there are equally good logical reasons for asserting that the world never had a beginning and that space is infinite. We can "prove" on paper, that God exists and that the soul is immortal. We can also "prove" on paper, that god does not exist and that the soul is not immortal. Again, did the world have a beginning in time? We cannot conceive eternity; but then, too, we cannot conceive any point in the past without feeling at once that before that, something was. Is there a first cause? Yes, for an endless chain is inconceivable. No, for a first cause uncaused is inconceivable also. We shall never have any experience which we shall not interpret in terms of space and time and cause: but we will never have any philosophy if we forget that these are not things, but modes of interpretation and understanding. Thus, what Kant calls "Transcendental Dialectic" reminds theology that substance and cause and necessity are finite categories; modes of arrangement and classification which the mind applies to sense-experience. It is reliably valid only for the phenomena which appears to such experience. We cannot apply these conceptions to the noumenal world. Anything that goes beyond experience generated by the mind is impossible of proof.

The priests of Germany were in wild protest against this philosophy which dealt a direct blow against their teaching. Heine, German poet and essayist, likened Kant to Robespierre: "The terrible Robespierre", he wrote, "killed a king and a few thousand Frenchmen - which could be forgiven. 'But Kant had killed God, had undermined the most precious arguments of theology."


Kant felt the necessity to reply to this outburst in which he had demonstrated that religion cannot be based on science or theology. This he did in a resort to ethics in his second critique, The critique of Practical Reason. This work was an attempt to replace the basis of theology for religion by replacing it with faith beyond the realm of reason. The moral basis of religion must be absolute, not derived from sense-experience: not corrupted by reason, but derived from the inner self by direct perception and intuition. A universal and necessary ethic had to be found, a priori principles of morals absolute and certain as mathematics. It must be shown that "pure reason can be practical: i.e., can of itself determine the will independently of anything empirical" (Critique of Practical Reason). That the moral sense is innate and not derived from experience. The moral imperative demanded as a basis for religion must be an absolute, a categorical imperative.
The categorical imperative seeks to show that midst the reality of all our experience, the moral sense produces an inescapable feeling in the face of temptation that this or that is wrong. We may yield; but the feeling remains there still. What is it that brings remorse and a new resolution: It is the categorical imperative within us, the unconditional demand of conscience to "act as if the maxim of our action were to become by our will a universal law of nature". We know - not by reasoning - but by vivid and immediate feelings, that we must avoid behaviour which it adopted by all would render social life impossible. For instance, I may wish to cover up by a lie, but "while I can will the lie, I can by no means will that lying should be universal. For with such a law there would be no promises at all."

We perceive that life does not follow those dramas so liked by the people, in which the villain is punished and acts of virtue rewarded. We are fully aware that any thief can triumph it he is able to steal enough. That honesty is far from being the best policy. Yet knowing all this, we still feel the command to be righteous. Finally, there is a God. If the sense of doing one's duty justifies belief in a reward to come, "the postulate of immortality ... must lead to the supposition of the existence of a cause adequate to this effect; in other words, it must postulate the existence of God". (The sentences in quotes in this section are all from Kant's Critique of Practical Reason).

Whether or not Kant sought to appease the opposing forces against him with his categorical imperative, he does not show this with his follow-up essay on religion. In this he states that Christ had brought the kingdom of God nearer to earth, but it was misunderstood. Instead, the kingdom of the priest has been established among us. Instead of men being bond together by religion they are divided into a thousand sects. Again, miracles cannot prove a religion, for we can never quite rely on the testimony which supports them: and prayer is useless if it aims at a suspension of the natural laws which hold for all experience.

The result of this audacity was that Kant received an order from the Prussian King which read; "Our highest person has been greatly displeased to observe how you misuse your philosophy to undermine and destroy many of the most important and fundamental doctrines of Holy Scriptures and of Christianity. We demand of you immediately an exact account, and expect that in future you will give no such cause of offense, but rather, in accordance with your duty, you will employ your talents and authority so that our paternal purpose may be more and more attained. If you continue to oppose this order you may expect unpleasant consequences. (Encyclopaedia Britannica, article, Frederick William II). Kant replied that every scholar had the right to form independent judgements on religious matters, and to make his opinions known; but that during the reign of the present king he would preserve silence.

[to be continued]
  • #3
Immanuel Kant [part 3]


Some criticisms of Kant's philosophy

Plekhanov sees a contradiction in Kant's "Thing in itself". If the phenomenon is caused by the action upon us of the thing in itself, he states, then the action of this thing is the cause of the phenomenon. Yet according to Kant the category of causality is only applicable within the limits of the world of phenomena and is entirely inapplicable to the thing in itself. Thus the contradiction is established in that either we continue to consider that causality is inapplicable to the thing in itself and consequently reject the thought that the phenomenon is brought forth by the action upon us of the thing in itself: or, we continue to consider this thought as correct and then admit that the category of causality is applicable to things in themselves. In the first case we take the road of subjective idealism. In the second, materialism. Materialism does not insist that we know the things in themselves independently of their action upon us. It only maintains that these things are known by the way in which we act upon them through our senses.
Again Plekhanov: "So things in themselves have no appearance at all. Their appearance exists only in the consciousness of those subjects on whom they act. What subjects? - People? No, not only people but all organisms which have the possibility to see the external world. The snail will not see things as we do - does not follow that the properties of the external world have only a subjective significance. If a man and a snail move through the distance from A to B along a straight line it is still the shortest distance between two points. If both went along a broken line they would both have to expend a greater amount of labor for their advance. Consequently the properties of space have objective significance. Although seen differently by different organisms at different stages of development. Further, development takes place within time: yet Kant maintains that time is only subjective form of contemplation. Holding this view, I contradict myself if speak of what is before me, i.e. when I did not exist and consequently neither did the forms of my contemplation, space and time. If people exist outside men, then that outside me appears to my brain as space. So that space is not only a subjective form of contemplation but objective. Suppose we transport ourselves to the time of our remote ancestors. How did the matter of space, time and causality appear then? Whose subjective forms where they? Prehistoric animals!

Idealism says where there is no subject there can be no object. The history of the Earth SHOWS THAT the object existed long before the subject appeared. Idealism says: reason dictated its laws to nature. History of the organic world shows that "reason' appears only on a higher rung of the ladder of development. This development can only be explained by the laws of nature, it follows, therefore, that nature dictated its laws to reason. Thus the theory of development reveals the truth of materialism. The history of mankind is a particular case of development in general.

Although we have yet to study Hegel, it is noteworthy that he was critical of Kant's categorical imperative. He takes examples of this imperative we have not made reference to such as suicide. Kant cites the example of a particular man who is unhappy with life and he asks whether it is permissible for him to kill himself. Kant's categorical imperative would answer no; for if suicide was made a universal law, what would happen is that life would cease. Therefore suicide does not conform to morality. Another example, somebody trusts his property for safe keeping to another man. Is it permissible for this other man to keep it for himself? The answer comes from the categorical imperative: if all people appropriated what they had been entrusted with to them nobody would give property for safe keeping.

Hegel replies to the question of suicide that this is a question not of all people generally, but only of such as are broken by the difficult struggle of life, and the suicide of such people would in no way end life. Hegel extracts from this proposition of Kant that his categorical imperative does not contain a single law of morality clear in itself, without any further arguments and without contradictions independently of other qualifications. On the safe keeping of others property, Hegel asks: What is the harm it things are not entrusted for safe keeping? And it anyone replied that it would be more difficult to guard chattels and that property itself would be impossible in the end, it could also be objected, what is property needed for?

With Kant, says Hegel, each definite law of morality is an empty statement, a meaningless tautology like the formula A = A, chattels entrusted for safe keeping are chattels entrusted for safe keeping, property is property. For Kant there existed no such questions as those which Hegel counterposes to his "empty statements": Where is the harm it things are not entrusted for safe keeping? Why is property needed? Kant's ideal, his "Kingdom of aims" adds Plekhanov, "was an abstract ideal of bourgeois society, whose standards seemed to Kant to be unquestionable orders of "practical Reason". Kant's morality is bourgeois morality. Worn thin now as capitalism becomes more brutal in its descending phase, as Trotsky observes Their Morals and Ours:

"The highest generalisation of these (moral) norms is the 'categorical imperative' of Kant. But in spite of the fact that it occupies a high position in the philosophic Olympus this imperative does not embody anything categoric because it embodies nothing concrete. It is a shell without content."

Commenting on Kant, Lenin remarked that: "The principal feature of the philosophy of Kant is an attempted reconciliation of materialism and idealism, a compromise between the claims of both, a fusion of heterogeneous and contrary philosophical tendencies into one system. When Kant admits that something outside us - a thing in itself - corresponds to our perceptions, he seems to be a materialist. When, however, he declares that this thing in itself is unknown ... he appears to be an idealist. Regarding experience as the only source of knowledge, Kant seems to be turning towards materialism. Recognising the a-priority of space, time and casuality, etc., Kant seems to be turning towards idealism."

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