Immanuel Kant was a Prussian philosopher from Koningsberg in the province of East Prussia.

Things in ThemselvesEdit

Kant wrote that knowledge begins with the senses then proceeds to the mind and so if we never experience something we can never be sure of whether or not it exists.

Bridging the GapEdit

Before Kant there was a long-running quarrel between rationalists (those who believed the mind to be superior in the acquiring of knowledge, usually from mainland Europe) and empiricists (those who believed the senses were superior in the acquiring of knowledge, usually British. Kant criticised both in The Critique of Pure Reason.[1]


Kant was in favour of the French Revolution but was horrified at the bloodshed therein The Giants of Philosophy:Immanuel Kant. Kant was a classical liberal (a moderate by today's standards.) He admired the Prussian king Frederick the Great and supported the Enlightenment [2].


  • Do only what you would will to be a universal law.

-the categorical imperative

  • Out of the crooked timber of humanity no straight thing was ever made.
  • Metaphysics is a rough sea with few lighthouses and many a philosophical wreck.
Religion Protestant and agnostic simultaneously (In the Critique of Pure Reason he wrote that he did believe in God, see also draft am sich)
Language German

Hitherto it has been assumed that all our knowledge must conform to objects. But all attempts to extend our knowledge of objects by establishing something in regard to them a priori, by means of concepts, have, on this assumption, ended in failure. We must therefore make trial whether we may not have more success in the tasks of metaphysics, if we suppose that objects must conform to our knowledge. This would agree better with what is desired, namely, that it should be possible to have knowledge of objects a priori, determining something in regard to them prior to their being given. This is Kant's Copernican revolution.(kBxvii)

Examples are necessary only from a popular point of view, and this work can never be made suitable for popular consumption. Examples as aids to clearness may be of assistance in regard to details they often interfere with our grasp of the whole(kAxix)

There is a contradiction between free and not free if the distinction between things-in-themselves and appearances is not made(kBxxvii)

The primary use of critique is negative in that it warns we must never venture with speculative reason beyond experience(kBxxix)

Dogmatism is the presumption that it is possible to make progress with pure knowledge according to principles from concepts alone(kBxxxvi)

If we have a proposition which in being thought is thought as necessary, it is an a priori judgment(kB3)

Pure reason is that which contains the principles whereby we know anything absolutely a priori(kA11)

General Logic abstracts from all content of the predicate. Transcendental logic considers the content of a logical affirmation that is thus made by means of a merely negative predicate(kA12)

Judgments of experience are all synthetic (kB12)

All mathematical judgments are synthetic(kB14)

Morality has no place in transcendental philosophy because it contains motives and these belong to the empirical sources of knowledge(kA15)

The concept of the sum of 7 and 5 contains nothing save the union of the two numbers into one. The concept of 12 is by no means already thought in merely thinking this union of 7 and 5(kB15)

Sensibility contains that conditions under which the objects of human knowledge are given(kA16)

A proposition of geometry is a synthetic judgment(kB16)

Physics contains a priori synthetic judgments as principles(kB17)

Metaphysics consists at least in intention, entirely of a priori synthetic propositions(kB18)

The transcendental aesthetic is the science of all principles of a priori sensibility to be distinguished from transcendental logic which deals with the principles of pure thought(kA22)

Our exposition therefore establishes the reality of space in respect of whatever can be presented to us outwardly as an object but also the ideality of space without regard to the constitution of our sensibility(kA28)

Sensibility is receiving representations of objects(kB34)

Intuition is a mode of knowledge in immediate relation to objects(kB34)

Time and space are two sources of knowledge from which bodies of a priori synthetic knowledge can be derived(kB55)

Transcendental aesthetic cannot contain more than these two elements (space and time)(kB58)

If the manifold of which space and time consists is to be known, the spontaneity of our thought requires that it be gone through in a certain way, taken up, and connected. This act I name synthesis(kB103)

To bring this synthesis to concepts is a function which belongs to the understanding and it is through this function of the understanding that we first obtain knowledge properly so called. By means of analysis different representations are brought under one concept. A procedure treated of in general Logic, Transcendental logic teaches how we bring to concepts the pure synthesis of representations(kB104)

The explanation of the manner in first concepts can thus relate a priori to objects I entitle their transcendental deduction which shows the manner in which a concept is acquired through experience(kB118)

Combination is an act of the understanding. Synthesis is ourselves combining(kB130)

Only after combination by the understanding can anything that allows of analysis be given to the faculty of representation(kB131)

That representation that can be given prior to all thought to entitled intuition(kB132)

The transcendental unity of apperception is that unity through which all the manifold given in an intuition is united in a concept of the object(kB139)

Examples often weaken that effort which is required of the understanding to comprehend properly the rules in their universality(kB174)

The principles of mathematical employment will therefore be unconditionally necessary, that is, apodeictic(kB200)

The number 12 is generated through the synthesis of 7 with 5. Such propositions must not be called axioms (that would involve recognition of an infinite number of axioms), but numerical formulas(kB206)

That which agrees with the formal conditions of experience, that is, with the conditions of intuition and of concepts, is possible. That which is bound up with the material conditions of experience, that is, with sensation, is actual. That which in its connection with the actual is determined in accordance with universal conditions of experience, is (that is, exists as) necessary(kB266)

Inner experience is itself possible only mediately, and only through outer experience(kB277)

A noumenon is an object determinable through mere concepts(kA285)

The concept of a noumenon is problematic, that is, it is the representation of a thing of which we can neither say that it is possible nor that it is impossible; for we are acquainted with no kind of intuition but our own sensible kind and no kind of concepts but the categories, and neither of those is appropriate to a non-sensible subject. We cannot positively extend the sphere of the objects of our own thought beyond the conditions of our sensibility, and assume besides appearances objects of pure thought, that is, noumena, since such objects have no assignible positive meaning(kA287)

In cases where this unity of time is not to be found, and therefore in the case of the noumenon, all employment, and indeed the whole meaning of the categories entirely vanishes(kB308)

Just as we have entitled the pure concepts of understanding categories, so we shall give a new name to the concepts of pure reason, calling them transcendental ideas(k309)

The division of objects into phenomena and noumena is inadmissible(kB311)

What our understanding acquires through this concept of a noumenon is a negative extension, that is to say, understanding is not limited through sensibility; on the contrary, it itself limits sensibility by applying the term noumena to things in themselves (things not regarded as appearances) (kB312)

A logical paralogism is a syllogism which is fallacious in form, be its content what it may. A transcendental paralogism is one in which there is a transcendental ground, constraining us to draw a formally invalid conclusion. Such a fallacy is therefore grounded in the nature of human reason, and gives rise to an illusion which cannot be avoided, although it may indeed be rendered harmless(k329)

If I remove the thinking subject the whole corporeal world must at once vanish: it is nothing save an appearance in the sensibility of our subject and a mode of its representations(k354)

The transcendental ideas are thus simply categories extended to the unconditioned(k386)

The antithetic treats only of the conflict of the doctrines of reason with one another and the causes of this conflict. The transcendental antithetic is an inquiry into the antimony of pure reason, its causes and outcome(k393)

I cannot think a totality either prior to the synthesis or by means of the synthesis. For the concept of totality is in this case itself the representation of a completed synthesis of the parts. And since this completion is impossible, so likewise is the concept of it(k402)

The cosmological ideas are such that an object congruent with them can never be given in any possible experience, and that even in thought reason is unable to bring them into harmony with the universal laws of nature. Yet they are not arbitrarily conceived. Reason, in the continuous advance of empirical synthesis, is necessarily led up to them whenever it endeavors to free from all conditions and apprehend in its unconditioned totality that which according to the rules of experience can never be determined save as conditioned(k422)

Transcendental idealism realizes that since space is a form of that intuition which we entitle outer, and since without objects in space there would be no empirical representation whatsoever, we can and must regard the extended beings in it as real; and the same is true of time. But this space and this time, and with them all appearances, are not in themselves things; they are nothing but representations, and cannot exist outside our mind(k440)

Empirical idealism admits the genuine reality of space, but denies (or doubts) the existence of extended beings in it, and so does not in this regard allow of any properly demonstrable distinction between truth and dreams(k440)

The principle of reason is thus only properly a rule, prescribing a regress in the series of the conditions of given appearances, and forbidding it to bring the regress to a close by treating anything at which it may arrive as absolutely unconditioned(k450)

This rule of pure reason cannot tell us what the object is, but only how the empirical regress is to be carried out so as to arrive at the complete concept of the object(k451)

In the empirical regress we can have no experience of an absolute limit, that is, no experience of any condition as being one that empirically is absolutely unconditioned. The reason is this: such an experience would have to contain a limitation of appearances by nothing, or by the void, and in the continual regress we should have to be able to encounter this limitation in a perception- which is impossible(k455)

Whatever is an object of the senses is not itself appearance, I entitle intelligible. The causality of this being can be regarded from two points of view. Regarded as the causality of a thing-in-itself, it is intelligible in its action; regarded as the causality of an appearance in the world of sense, it is sensible in its effects(k467)

In as much as it is noumenon, nothing happens in it; there can be no change requiring dynamical determination in time, and therefore no causal dependence upon appearances(k469)

The dynamical regress is distinguished in an important respect from the mathematical. Since the mathematical regress is concerned only with the combining of parts to form a whole or the division of a whole into parts, the conditions of this series must always be regarded as parts of the series, and therefore as homogeneous and as appearances. In the dynamical regress on the other hand, we are concerned, not with possibility of an unconditioned whole of given parts, or with an unconditioned part for a given whole, but with the derivation of a state from its cause, or of the contingent existence of substance itself from necessary existence. In this latter regress, it is not therefore, necessary that the condition should form part of an empirical series along with the conditioned(k480)

It is evident that since everything in the sum-total of appearances is alterable, and therefore conditioned in its existence, there cannot be in the whole series of dependent existence any unconditioned member the existence of which can be regarded as absolutely necessary. Hence, if appearances were things in themselves, and if, as would follow, the condition and the conditioned always belonged to one and the same series of intuitions, by no possibility could a necessary being exist as the condition of the existence of appearances in the world of sense(k480a)

Either reason through its demand for the unconditioned must remain in conflict with itself, or this unconditioned must be posited outside the series, in the intelligible(k482)

Things of which as they are in themselves we have not the least knowledge, consequently the only resource we have remaining to us is the use of analogy, by which we employ the concepts of experience in order to form some sort of concept of intelligible things(k484)

Ideas are even further removed from objective reality than are categories, for no appearance can be found in which they can be represented in concreto(k485a)

By the ideal I understand the idea, not merely in concreto, but in individuo, that is as an individual thing, determinable or even determined by the idea alone(k485b)

Human reason contains not only ideas, but ideals also, which although they do not have, like the Platonic ideas, creative power, yet have practical power(as regulative principles), and form the basis of the possible perfection of certain actions. We cannot concede to these ideals objective reality(existence)(k486)

Reason, in employing the transcendental ideal as that by reference to which it determines all possible things, is proceeding in a manner analogous with its procedure in disjunctive syllogisms. This, indeed, is the principle upon which I have based the systematic division of all transcendental ideas, as parallel with, and corresponding to, the three kinds of syllogism(k491)

Notwithstanding this pressing need of reason to presuppose something that may afford the understanding a sufficient foundation for the complete determination of its concepts, it is yet much too easily conscious of the ideal and merely fictitious character of such a presupposition to allow itself, on this ground alone, to be persuaded that a mere creature of its own thought is a real being- were it not that it is impelled from another direction to seek a resting place in the regress from the conditioned, which is given, to the unconditioned(k495)

If we admit that all existential propositions are synthetic, how can we profess to maintain that the predicate of existence cannot be rejected without contradiction? This is a feature which is found only in analytic propositions, and is indeed precisely what constitutes their analytic character(k504)

Synthetic a priori knowledge is possible only in so far as it expresses the formal conditions of a possible experience; and all principles are therefore only of immanent validity, that is they are applicable only to objects of empirical knowledge, to appearances(k529)

Transcendental ideas are just as natural to reason as the categories are to understanding- though with this difference, that while the categories lead to truth, that is, to the conformity of our concepts with the object, the ideas produce what, though a mere illusion, is nonetheless irresistible(k532)

If it can be shown that the three transcendental ideas (the psychological, the cosmological, and the theological) although they do not directly relate to, or determine, any object corresponding to them, none the less, as rules of the empirical employment of reason, lead us to systematic unity, under the presupposition of such an object in the idea; and that they thus contribute to the extension of empirical knowledge, without ever being in a position to run counter to it, we may conclude that it is a necessary maxim of reason to proceed always in accordance with such ideas(k550)

Under the guidance of inner experience, we connect all the appearances, all the actions and receptivity of our mind, as if the mind were a simple substance which persists with personal identity, while its states, to which those of the body belong only as outer conditions, are in continual change(k551)

Teleology is intended to aid us merely in completing the unity of nature in accordance with universal laws(k563)

The criticism of reason, whereby not its present bounds, but its determinate and necessary limits, not its ignorance on this or that point but its ignorance in regard to all possible questions of a certain kind, is demonstrated from principles(k607)

In the transcendental analytic, we derived the principle that everything which happens has a cause, from the condition under which alone a concept of happening in general is objectively possible- namely, by showing that the determination of an event I time, and therefore the event as belonging to experience would be impossible save as standing under such a dynamical rule(k624)

The dogmatist’s purpose, when he comes forward with ten proofs, can only be that of the parliamentary advocate, who intends his various arguments for different groups, in order to take advantage of the weakness of those before whom he is pleading- hearers who, without entering deeply into the matter, desire to be soon quit of it and therefore seize upon whatever may first happen to attract their attention, and decide accordingly(k625)

The ultimate aim to which to speculation of reason in its transcendental employment is directed concerns three objects: The freedom of the will, the immortality of the soul, and the existence of God(k631)

…in concreto, that is, in the study of nature(k631)

The whole equipment of reason is in fact determined with a view to the three above mentioned problems. These, however, themselves in turn refer us yet further, namely, to the problem what we ought to do, if the will is free, if there is a God and a future world(k632)

In the precepts of prudence, the whole business of reason consists in uniting all of the ends which are prescribed to us by our desires in the one single end, happiness, and in coordinating the means for attaining it(k632)

If then, these three propositions are not in any way necessary for knowledge, and are yet strongly recommended by our reason, their importance, properly regarded, must concern only the practical. By ‘the practical’ I mean everything that is possible through freedom(k632b)

By a system I understand the unity of the manifold modes of knowledge under one idea(k653)

How is synthetic a priori knowledge possible? The answer is this: We take nothing more from experience than is required to give us an object of outer or of inner sense. The object of outer sense we obtain through the mere concept of matter(impenetrable, lifeless extension), the object of inner sense through the concept of a thinking being(in the empirical inner representation, ‘I think’)(k663)

Kant spoke of himself as having affected a 'Copernican Revolution', but he would have been more accurate if he had spoken of a 'Ptolemaic counter-revolution', since he put Man back at the center from which Copernicus had dethroned him(hk9)

'Synthetic' is any proposition which is not part of mathematics or deductive Logic(hk516)

If the doctrine that all our synthetic knowledge is based on experience is true, it cannot be known since it is a universal proposition of just the sort that experience alone cannot prove(hk525)

Gottlob Frege showed in detail how arithmetic can be deduced from pure logic, without the need of any fresh ideas or axioms, thus disproving Kant's assertion that '7 + 5 = 12' is synthetic(lk324)

Idealists used to say that relations are the work of the mind; and Kant imagined that real things are not in space or time, but spatio-temporal order is created by our subjective apparatus(mpd128)

Kant professes to prove both the world has no beginning and no limits in space, but is infinite in respect of both time space and the opposite, whereas, if what we have said on modern Logic has any truth, it must be impossible to prove either(okew160)

The essential thing about space is spatial order, and mere points, by themselves, will not account for spatial order. It is obvious that his argument assumes absolute space; but it is spatial relations that are alone important, and they cannot be reduced to points. This ground for his view depends, therefore, upon his ignorance of the logical theory of order and his oscillations between absolute and relative space(okew163)

Kant, in his first antinomy, seems to hold that it is harder for the past to be infinite than for the future to be so, on the ground that the past is now completed, and nothing infinite can be completed. It is very difficult to see how he can have imagined that there was any sense in this remark but it seems most probable that he was thinking of the infinite as the 'unended'(okew185)

Kant, in his first published work, points out the circularity of Leibniz's deduction in the above passage of the Theodicee, and proceeds, being still a Leibnizian, to infer that the number of dimensions is synthetic and contingent, and might be different in other possible worlds(pl22)

The Kantian view asserted that mathematical reasoning is not strictly formal, but always uses intuitions, i.e. the a priori knowledge of space and time. Thanks to the progress of symbolic logic, especially as treated by Peano, this part of the Kantian philosophy is now capable of a final and irrevocable refutation(pm4)

For all algebra and analysis, it is unnecessary to assume any material beyond the integers which can themselves be defined in logical terms. It is this far more than non-Euclidean geometry, that is really fatal to the Kantian theory of a priori intuitions as the basis of mathematics(pm158)

Credit is undoubtedly due to Kant for having first called attention to the logical importance of asymmetrical relations(pm227)

Time is the source of arithmetic, space of geometry. It is only in the forms of time and space that objects can be experienced by a subject; and thus pure mathematics must be applicable to all experience(pm456)

Kant never doubted for a moment that the propositions of Logic are analytic, whereas he rightly perceived that those of mathematics are synthetic. It has since appeared that logic is just as synthetic as all other kinds of truth(pm457)

Although it would seem that Kant, in the Transcendental Aesthetic, inclines towards absolute position in space, in yet another book he quite definitely adopts the relational view(pm489)

Kant's intent, evident more from the use he makes of the notion of analyticity than from his definition of it, can be restated thus : a statement is analytic when it is true by virtue of meanings and independently of fact. This formulation has two shortcomings: it limits itself to statements of subject-predicate form, and it appeals to a notion of containment which is left at a metaphorical level(flpov21)

Kant accepted the empiricist's premise that all knowledge begins with our experiences of the world, but he also believed human beings possess certain innate knowledge that is necessary for any thought to take place at all. There are thus two components that come together in the process of thinking: sense data and a priori knowledge. Kant used his theory to explore the limits of what human beings, by the very nature of their powers of observation and reasoning, could ever hope to know(mg32)

Kant asserted that there have to be some true synthetic a priori propositions for any process of thought concerned with an objective world. These synthetic a prioris would have to be true independently of the contingent features of the world-i.e., they must be true in any world(mg186)

Mysticism and Logic

Problems of Philosophy

[[Category:Enlightenment]] [[Category:Misanthropes]] [[Category:Kantianism]] [[Category:Protestants]] [[Category:Agnostics]] [[Category:Classical liberals]] [[Category: Prussians]]