Young scholar

Kant showed a great aptitude for study at an early age. He first attended the Collegium Fridericianum, from which he graduated at the end of the summer of 1740. In 1740, aged 16, he enrolled at the University of Königsberg, where he would later remain for the rest of his professional life.^[19] He studied the philosophy of Gottfried Leibniz and Christian Wolff under Martin Knutzen (Associate Professor of Logic and Metaphysics from 1734 until he died in 1751), a rationalist who was also familiar with developments in British philosophy and science and introduced Kant to the new mathematical physics of Isaac Newton. Knutzen dissuaded Kant from the theory of pre-established harmony, which he regarded as "the pillow for the lazy mind".^[20] He also dissuaded Kant from idealism, the idea that reality is purely mental, which most philosophers in the 18th century regarded negatively. The theory of transcendental idealism that Kant later included in the Critique of Pure Reason was developed partially in opposition to traditional idealism.

Kant had contacts with students, colleagues, friends and diners who frequented the local Masonic lodge.^[21]

His father's stroke and subsequent death in 1746 interrupted his studies. Kant left Königsberg shortly after August 1748;^[22] he would return there in August 1754.^[23] He became a private tutor in the towns surrounding Königsberg, but continued his scholarly research. In 1749, he published his first philosophical work, Thoughts on the True Estimation of Living Forces (written in 1745–1747).^[24]

Early work

Kant is best known for his work in the philosophy of ethics and metaphysics, but he made significant contributions to other disciplines. In 1754, while contemplating on a prize question by the Berlin Academy about the problem of Earth's rotation, he argued that the Moon's gravity would slow down Earth's spin and he also put forth the argument that gravity would eventually cause the Moon's tidal locking to coincide with the Earth's rotation.^{[lower-alpha 2][26]} The next year, he expanded this reasoning to the formation and evolution of the Solar System in his Universal Natural History and Theory of the Heavens.^[26] In 1755, Kant received a license to lecture in the University of Königsberg and began lecturing on a variety of topics including mathematics, physics, logic, and metaphysics. In his 1756 essay on the theory of winds, Kant laid out an original insight into the Coriolis force.

In 1756, Kant also published three papers on the 1755 Lisbon earthquake.^[27] Kant's theory, which involved shifts in huge caverns filled with hot gases, though inaccurate, was one of the first systematic attempts to explain earthquakes in natural rather than supernatural terms. In 1757, Kant began lecturing on geography making him one of the first lecturers to explicitly teach geography as its own subject.^[28][29] Geography was one of Kant's most popular lecturing topics and, in 1802, a compilation by Friedrich Theodor Rink of Kant's lecturing notes, Physical Geography, was released. After Kant became a professor in 1770, he expanded the topics of his lectures to include lectures on natural law, ethics, and anthropology, along with other topics.^[28]

Kant's house in Königsberg in an 1842 painting

In the Universal Natural History, Kant laid out the nebular hypothesis, in which he deduced that the Solar System had formed from a large cloud of gas, a nebula. Kant also correctly deduced that the Milky Way was a large disk of stars, which he theorized formed from a much larger spinning gas cloud. He further suggested that other distant "nebulae" might be other galaxies. These postulations opened new horizons for astronomy, for the first time extending it beyond the solar system to galactic and intergalactic realms.^[30]

From then on, Kant turned increasingly to philosophical issues, although he continued to write on the sciences throughout his life. In the early 1760s, Kant produced a series of important works in philosophy. The False Subtlety of the Four Syllogistic Figures, a work in logic, was published in 1762. Two more works appeared the following year: Attempt to Introduce the Concept of Negative Magnitudes into Philosophy and The Only Possible Argument in Support of a Demonstration of the Existence of God. By 1764, Kant had become a notable popular author, and wrote Observations on the Feeling of the Beautiful and Sublime; he was second to Moses Mendelssohn in a Berlin Academy prize competition with his Inquiry Concerning the Distinctness of the Principles of Natural Theology and Morality (often referred to as "The Prize Essay"). In 1766 Kant wrote a critical piece on Emanuel Swedenborg's Dreams of a Spirit-Seer.

In 1770, Kant was appointed Full Professor of Logic and Metaphysics at the University of Königsberg. In defense of this appointment, Kant wrote his inaugural dissertation On the Form and Principles of the Sensible and the Intelligible World^{[lower-alpha 3]} This work saw the emergence of several central themes of his mature work, including the distinction between the faculties of intellectual thought and sensible receptivity. To miss this distinction would mean to commit the error of subreption, and, as he says in the last chapter of the dissertation, only in avoiding this error does metaphysics flourish.

It is often claimed that Kant was a late developer, that he only became an important philosopher in his mid-50's after rejecting his earlier views. While it is true that Kant wrote his greatest works relatively late in life, there is a tendency to underestimate the value of his earlier works. Recent Kant scholarship has devoted more attention to these "pre-critical" writings and has recognized a degree of continuity with his mature work.^[31]

Publication of The Critique of Pure Reason

At age 46, Kant was an established scholar and an increasingly influential philosopher, and much was expected of him. In correspondence with his ex-student and friend Markus Herz, Kant admitted that, in the inaugural dissertation, he had failed to account for the relation between our sensible and intellectual faculties.^[32] He needed to explain how we combine what is known as sensory knowledge with the other type of knowledge—that is, reasoned knowledge—these two being related, but having very different processes.

Portrait of philosopher David Hume

Kant also credited David Hume with awakening him from a "dogmatic slumber" in which he had unquestioningly accepted the tenets of both religion and natural philosophy.^[33][34] Hume, in his 1739 Treatise on Human Nature, had argued that we only know the mind through a subjective, essentially illusory series of perceptions. Ideas such as causality, morality, and objects are not evident in experience, so their reality may be questioned. Kant felt that reason could remove this skepticism, and he set himself to solving these problems. Although fond of company and conversation with others, Kant isolated himself, and resisted friends' attempts to bring him out of his isolation.^{[lower-alpha 4]} When Kant emerged from his silence in 1781, the result was the Critique of Pure Reason. Kant countered Hume's empiricism by claiming that some knowledge exists inherently in the mind, independent of experience.^[33] He drew a parallel to the Copernican revolution in his proposal that worldly objects can be intuited a priori, and that intuition is consequently distinct from objective reality. He acquiesced to Hume somewhat by defining causality as a "regular, constant sequence of events in time, and nothing more".^[36]

Although now recognized as one of the greatest works in the history of philosophy, the Critique disappointed Kant's readers upon its initial publication.^[37] The book was long, over 800 pages in the original German edition, and written in a convoluted style. Kant was quite upset with its reception.^[38] His former student, Johann Gottfried Herder criticized it for placing reason as an entity worthy of criticism instead of considering the process of reasoning within the context of language and one's entire personality.^[39] Similar to Christian Garve and Johann Georg Heinrich Feder, he rejected Kant's position that space and time possessed a form that could be analyzed. Additionally, Garve and Feder also faulted Kant's Critique for not explaining differences in perception of sensations.^[40] Its density made it, as Herder said in a letter to Johann Georg Hamann, a "tough nut to crack", obscured by "all this heavy gossamer".^[41] Its reception stood in stark contrast to the praise Kant had received for earlier works, such as his Prize Essay and shorter works that preceded the first Critique. Recognizing the need to clarify the original treatise, Kant wrote the Prolegomena to any Future Metaphysics in 1783 as a summary of its main views. Shortly thereafter, Kant's friend Johann Friedrich Schultz (1739–1805), a professor of mathematics, published Explanations of Professor Kant's Critique of Pure Reason (Königsberg, 1784), which was a brief but very accurate commentary on Kant's Critique of Pure Reason.^[42]

Engraving of Immanuel Kant

Kant's reputation gradually rose through the latter portion of the 1780s, sparked by a series of important works: the 1784 essay, "Answer to the Question: What is Enlightenment?"; 1785's Groundwork of the Metaphysics of Morals (his first work on moral philosophy); and, from 1786, Metaphysical Foundations of Natural Science. But Kant's fame ultimately arrived from an unexpected source. In 1786, Karl Leonhard Reinhold published a series of public letters on Kantian philosophy.^[43] In these letters, Reinhold framed Kant's philosophy as a response to the central intellectual controversy of the era: the pantheism controversy. Friedrich Jacobi had accused the recently deceased Gotthold Ephraim Lessing (a distinguished dramatist and philosophical essayist) of Spinozism. Such a charge, tantamount to atheism, was vigorously denied by Lessing's friend Moses Mendelssohn, leading to a bitter public dispute among partisans. The controversy gradually escalated into a debate about the values of the Enlightenment and the value of reason.

Reinhold maintained in his letters that Kant's Critique of Pure Reason could settle this dispute by defending the authority and bounds of reason. Reinhold's letters were widely read and made Kant the most famous philosopher of his era.

Later work

Kant published a second edition of the Critique of Pure Reason in 1787, heavily revising the first parts of the book. Most of his subsequent work focused on other areas of philosophy. He continued to develop his moral philosophy, notably in 1788's Critique of Practical Reason (known as the second Critique), and 1797's Metaphysics of Morals. The 1790 Critique of the Power of Judgment (the third Critique) applied the Kantian system to aesthetics and teleology.

In 1792, Kant's attempt to publish the Second of the four Pieces of Religion within the Bounds of Bare Reason,^[44] in the journal Berlinische Monatsschrift, met with opposition from the King's censorship commission, which had been established that same year in the context of the French Revolution.^[45] Kant then arranged to have all four pieces published as a book, routing it through the philosophy department at the University of Jena to avoid the need for theological censorship.^[45] This insubordination earned him a now-famous reprimand from the King.^[45] When he nevertheless published a second edition in 1794, the censor was so irate that he arranged for a royal order that required Kant never to publish or even speak publicly about religion.^[45] Kant then published his response to the King's reprimand and explained himself in the preface of The Conflict of the Faculties.^[45]

Kant with friends, including Christian Jakob Kraus, Johann Georg Hamann, Theodor Gottlieb von Hippel and Karl Gottfried Hagen

He also wrote a number of semi-popular essays on history, religion, politics, and other topics. These works were well received by Kant's contemporaries and confirmed his preeminent status in eighteenth-century philosophy. There were several journals devoted solely to defending and criticizing Kantian philosophy. Despite his success, philosophical trends were moving in another direction. Many of Kant's most important disciples and followers (including Reinhold, Beck, and Fichte) transformed the Kantian position. The progressive stages of revision of Kant's teachings marked the emergence of German idealism. Kant opposed these developments and publicly denounced Fichte in an open letter in 1799.^[46] It was one of his final acts expounding a stance on philosophical questions.

In 1800, a student of Kant named Gottlob Benjamin Jäsche (1762–1842) published a manual of logic for teachers called Logik, which he had prepared at Kant's request. Jäsche prepared the Logik using a copy of a textbook in logic by Georg Friedrich Meier entitled Excerpt from the Doctrine of Reason, in which Kant had written copious notes and annotations. The Logik has been considered of fundamental importance to Kant's philosophy, and the understanding of it. The great 19th-century logician Charles Sanders Peirce remarked, in an incomplete review of Thomas Kingsmill Abbott's English translation of the introduction to Logik, that "Kant's whole philosophy turns upon his logic."^[47] Also, Robert Schirokauer Hartman and Wolfgang Schwarz wrote in the translators' introduction to their English translation of the Logik, "Its importance lies not only in its significance for the Critique of Pure Reason, the second part of which is a restatement of fundamental tenets of the Logic, but in its position within the whole of Kant's work."^[48]

Death and burial

Kant's health, long poor, worsened. He died at Königsberg on 12 February 1804, uttering "Es ist gut" (It is good) before expiring.^[49] His unfinished final work was published as Opus Postumum. Kant always cut a curious figure in his lifetime for his modest, rigorously scheduled habits, which have been referred to as clocklike. However, Heinrich Heine noted the magnitude of "his destructive, world-crushing thoughts" and considered him a sort of philosophical "executioner", comparing him to Robespierre with the observation that both men "represented in the highest the type of provincial bourgeois. Nature had destined them to weigh coffee and sugar, but Fate determined that they should weigh other things and placed on the scales of the one a king, on the scales of the other a god."^[50]

When his body was transferred to a new burial spot, his skull was measured during the exhumation and found to be larger than the average German male's with a "high and broad" forehead.^[51] His forehead has been an object of interest ever since it became well known through his portraits: "In Döbler's portrait and in Kiefer's faithful if expressionistic reproduction of it—as well as in many of the other late eighteenth- and early nineteenth-century portraits of Kant—the forehead is remarkably large and decidedly retreating."^[52]

Kant's tomb in Kaliningrad, Russia

Kant's mausoleum adjoins the northeast corner of Königsberg Cathedral in Kaliningrad, Russia. The mausoleum was constructed by the architect Friedrich Lahrs and was finished in 1924, in time for the bicentenary of Kant's birth. Originally, Kant was buried inside the cathedral, but in 1880 his remains were moved to a neo-Gothic chapel adjoining the northeast corner of the cathedral. Over the years, the chapel became dilapidated and was demolished to make way for the mausoleum, which was built on the same location.

The tomb and its mausoleum are among the few artifacts of German times preserved by the Soviets after they captured the city.^[53] Today, many newlyweds bring flowers to the mausoleum. Artifacts previously owned by Kant, known as Kantiana, were included in the Königsberg City Museum. However, the museum was destroyed during World War II. A replica of the statue of Kant that in German times stood in front of the main University of Königsberg building was donated by a German entity in the early 1990s and placed in the same grounds.

After the expulsion of Königsberg's German population at the end of World War II, the University of Königsberg where Kant taught was replaced by the Russian-language Kaliningrad State University, which appropriated the campus and surviving buildings. In 2005, the university was renamed Immanuel Kant State University of Russia. The name change was announced at a ceremony attended by President Vladimir Putin of Russia and Chancellor Gerhard Schröder of Germany, and the university formed a Kant Society, dedicated to the study of Kantianism. The university was again renamed in the 2010s, to Immanuel Kant Baltic Federal University.^[54]

Kant's critical project

Immanuel Kant by Carle Vernet (1758–1836)

Kant's 1781 (revised 1787) book the Critique of Pure Reason has often been cited as the most significant volume of metaphysics and epistemology in modern philosophy.^[65]

In the first Critique, and later on in other works as well, Kant frames the "general" and "real problem of pure reason" in terms of the following question: "How are synthetic judgments a priori possible?"^[66][67]

To parse this claim, it is necessary to define some terms. First, Kant makes a distinction in terms of the source of the content of knowledge:

1. Cognitions a priori: "cognition independent of all experience and even of all the impressions of the senses".
2. Cognitions a posteriori: cognitions that have their sources in experience—that is, which are empirical.^[68]

Second, he makes a distinction in terms of the form of knowledge:

1. Analytic proposition: a proposition whose predicate concept is contained in its subject concept; e.g., "All bachelors are unmarried", or "All bodies take up space". These can also be called "judgments of clarification".
2. Synthetic proposition: a proposition whose predicate concept is not contained in its subject concept; e.g., "All bachelors are alone", "All swans are white," or "All bodies have weight". These can also be called "judgments of amplification".^[69]

An analytic proposition is true by nature of strictly conceptual relations. All analytic propositions are a priori (it is analytically true that no analytic proposition could be a posteriori). By contrast, a synthetic proposition is one the content of which includes something new. The truth or falsehood of a synthetic statement depends upon something more than what is contained in its concepts. The most obvious form of synthetic proposition is a simple empirical observation.^[70]

Philosophers such as David Hume believed that these were the only possible kinds of human reason and investigation, which he called "relations of ideas" and "matters of fact".^[71] Establishing the synthetic a priori as a third mode of knowledge would allow Kant to push back against Hume's skepticism about such matters as causation and metaphysical knowledge more generally. This is because, unlike a posteriori cognition, a priori cognition has "true or strict...universality" and includes a claim of "necessity".^[72][70]

Kant himself regards it as uncontroversial that we do have synthetic a priori knowledge—most obviously, that of mathematics. That 7 + 5 = 12, he claims, is a result not contained in the concepts of seven, five, and the addition operation.^[73] Yet, although he considers the possibility of such knowledge to be obvious, Kant nevertheless assumes the burden of providing a philosophical proof that we have a priori knowledge in mathematics, the natural sciences, and metaphysics. It is the twofold aim of the Critique both to prove and to explain the possibility of this knowledge.^[74]

Christian Wolff (1679–1754), whose methodical principles of logical exposition are responsible for many of the formal qualities of Kant's works

Before turning to Kant's arguments in the body of the Critique, there are two more distinctions that must be introduced.

"There are", Kant says, "two stems of human cognition, which may perhaps arise from a common but to us unknown root, namely sensibility and understanding, through the first of which objects are given to us, but through the second of which they are thought."^[75]

Kant's term for the object of sensibility is intuition, and his term for the object of the understanding is concept. In general terms, the former is a non-discursive representation of a particular object, and the latter is a discursive (or mediate) representation of a general type of object.^[76] The conditions of possible experience require both intuitions and concepts, that is, the affection of the receptive sensibility and the actively synthesizing power of the understanding.^{[77][lower-alpha 5]} Thus the statement: "Thoughts without content are empty, intuitions without concepts are blind."^[79]

Kant's basic strategy in the first half of his book will be to argue that some intuitions and concepts are pure—that is, are contributed entirely by the mind, independent of anything empirical. Knowledge generated on this basis, under certain conditions, can be synthetic a priori. This insight is known as Kant's "Copernican revolution", because, just as Copernicus advanced astronomy by way of a radical shift in perspective, so Kant here claims do the same for metaphysics.^[80][81]

The second half of the Critique is the explicitly critical part. In this "transcendental dialectic", Kant argues that many of the claims of traditional rationalist metaphysics violate the criteria he claims to establish in the first, "constructive" part of his book.^[82][83] As Kant observes, "human reason, without being moved by the mere vanity of knowing it all, inexorably pushes on, driven by its own need to such questions that cannot be answered by any experiential use of reason".^[84] It is the project of "the critique of pure reason" to establish the limits as to just how far reason may legitimately so proceed.^[85]

The doctrine of transcendental idealism

The section of the Critique entitled "The transcendental aesthetic" introduces Kant's famous metaphysics of transcendental idealism. Something is "transcendental" if it is a necessary condition for the possibility of experience, and "idealism" denotes some form of mind-dependence that must be further specified. (The correct interpretation of Kant's own specification remains controversial.)^[86]

The metaphysical thesis, then, states that human beings only experience and know phenomenal appearances, not independent things-in-themselves, because space and time are nothing but the subjective forms of intuition that we ourselves contribute to experience.^[87][88]

Nevertheless, although Kant says that space and time are "transcendentally ideal"—the pure forms of human sensibility, rather than part of nature or reality as it exists in-itself—he also claims that they are "empirically real", by which he means "that 'everything that can come before us externally as an object' is in both space and time, and that our internal intuitions of ourselves are in time".^[89][87] However we may interpret Kant's doctrine, he clearly wishes to distinguish his position from the subjective idealism of Berkeley.^[90]

Paul Guyer, although critical of many of Kant's arguments in this section, nevertheless writes of the "Transcendental Aesthetic" that it "not only lays the first stone in Kant's constructive theory of knowledge; it also lays the foundation for both his critique and his reconstruction of traditional metaphysics. It argues that all genuine knowledge requires a sensory component, and thus that metaphysical claims that transcend the possibility of sensory confirmation can never amount to knowledge."^[91]

Kant's theory of judgment

Kant statue in the School of Philosophy and Human Sciences (FAFICH) in the Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil

Following the "Transcendental Analytic" is the "Transcendental Logic". Whereas the former was concerned with the contributions of the sensibility, the latter is concerned, first, with the contributions of the understanding ("Transcendental Analytic") and, second, with the faculty of reason as the source of both metaphysical errors and genuine regulatory principles ("Transcendental Dialectic").

The "Transcendental Analytic" is further divided into two sections. The first, "Analytic of Concepts", is concerned with establishing the universality and necessity of the pure concepts of the understanding (i.e., the categories). This section contains Kant's famous "transcendental deduction". The second, "Analytic of Principles", is concerned with the application of those pure concepts in empirical judgments. This second section is longer than the first and is further divided into many sub-sections.^[94]

Critique of metaphysics

The second of the two Divisions of "The Transcendental Logic", "The Transcendental Dialectic", contains the "negative" portion of Kant's Critique, which builds upon the "positive" arguments of the preceding "Transcendental Analytic" to expose the limits of metaphysical speculation. In particular, it is concerned to demonstrate as spurious the efforts of reason to arrive at knowledge independent of sensibility. This endeavor, Kant argues, is doomed to failure, which he claims to demonstrate by showing that reason, unbounded by sense, is always capable of generating opposing or otherwise incompatible conclusions.

Like "the light dove, in free flight cutting through the air, the resistance of which it feels", reason "could get the idea that it could do even better in airless space".^[113] Against this, Kant claims that, absent epistemic friction, there can be no knowledge.

Nevertheless, Kant's critique is not entirely destructive. He presents the speculative excesses of traditional metaphysics as inherent in our very capacity of reason. Moreover, he argues that its products are not without some (carefully qualified) regulative value.

Moral thought

Kant developed his ethics, or moral philosophy, in three works: Groundwork of the Metaphysics of Morals (1785), Critique of Practical Reason (1788), and Metaphysics of Morals (1797). With regard to morality, Kant argued that the source of the good lies not in anything outside the human subject, either in nature or given by God, but rather is only the good will itself. A good will is one that acts from duty in accordance with the universal moral law that the autonomous human being freely gives itself. This law obliges one to treat humanity—understood as rational agency, and represented through oneself as well as others—as an end in itself rather than (merely) as means to other ends the individual might hold.

Kant is known for his theory that all moral obligation is grounded in what he calls the "categorical imperative", which is derived from the concept of duty. He argues that the moral law is a principle of reason itself, not based on contingent facts about the world, such as what would make us happy; to act on the moral law has no other motive than "worthiness to be happy".^[124]

The categorical imperative

In his Groundwork, Immanuel Kant introduced the categorical imperative: "Act only in accordance with that maxim through which you at the same time can will that it become a universal law."

Kant makes a distinction between categorical and hypothetical imperatives. A hypothetical imperative is one that we must obey to satisfy contingent desires. A categorical imperative binds us regardless of our desires: for example, everyone has a duty to not lie, regardless of circumstances, even though it is sometimes in our narrowly selfish interest to do so. These imperatives are morally binding because they are based on reason, rather than contingent facts about an agent.^[129] Unlike hypothetical imperatives, which bind us insofar as we are part of a group or society which we owe duties to, we cannot opt out of the categorical imperative, because we cannot opt out of being rational agents. We owe a duty to rationality by virtue of being rational agents; therefore, rational moral principles apply to all rational agents at all times.^[130] Stated in other terms, with all forms of instrumental rationality excluded from morality, "the moral law itself, Kant holds, can only be the form of lawfulness itself, because nothing else is left once all content has been rejected".^[131]

Kant provides three formulations for the categorical imperative. He claims that these are necessarily equivalent, as all being expressions of the pure universality of the moral law as such.^[132] Many scholars, however, are not convinced.^[133]

The formulas are as follows:

• Formula of Universal Law:
  • "Act only in accordance with that maxim through which you at the same time can will that it become a universal law";^[134] alternatively,
    • Formula of the Law of Nature: "So act, as if the maxim of your action were to become through your will a universal law of nature."^[134]
• Formula of Humanity as End in Itself:
  • "So act that you use humanity, as much in your own person as in the person of every other, always at the same time as an end and never merely as a means".^[135]
• Formula of Autonomy:
  • "the idea of the will of every rational being as a will giving universal law",^[136] or "Not to choose otherwise than so that the maxims of one's choice are at the same time comprehended with it in the same volition as universal law";^[137] alternatively,
    • Formula of the Realm of Ends: "Act in accordance with maxims of a universally legislative member for a merely possible realm of ends."^[138][139]

Kant defines maxim as a "subjective principle of volition", which is distinguished from an "objective principle or 'practical law.'" While "the latter is valid for every rational being and is a 'principle according to which they ought to act[,]' a maxim 'contains the practical rule which reason determines in accordance with the conditions of the subject (often their ignorance or inclinations) and is thus the principle according to which the subject does act.'"^[140]

Maxims fail to qualify as practical laws if they produce a contradiction in conception or a contradiction in the will when universalized. A contradiction in conception happens when, if a maxim were to be universalized, it ceases to make sense, because the "maxim would necessarily destroy itself as soon as it was made a universal law".^[141] For example, if the maxim 'It is permissible to break promises' was universalized, no one would trust any promises made, so the idea of a promise would become meaningless; the maxim would be self-contradictory because, when it is universalized, promises cease to be meaningful. The maxim is not moral because it is logically impossible to universalize—that is, we could not conceive of a world where this maxim was universalized.^[142] A maxim can also be immoral if it creates a contradiction in the will when universalized. This does not mean a logical contradiction, but that universalizing the maxim leads to a state of affairs that no rational being would desire.

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In Towards Perpetual Peace: A Philosophical Project, Kant listed several conditions that he thought necessary for ending wars and creating a lasting peace. They included a world of constitutional republics.^[149] His classical republican theory was extended in the Doctrine of Right, the first part of the Metaphysics of Morals (1797).^[150] Kant believed that universal history leads to the ultimate world of republican states at peace, but his theory was not pragmatic. The process was described in Perpetual Peace as natural rather than rational:

What affords this guarantee (surety) is nothing less than the great artist nature (natura daedala rerum) from whose mechanical course purposiveness shines forth visibly, letting concord arise by means of the discord between human beings even against their will; and for this reason nature, regarded as necessitation by a cause the laws of whose operation are unknown to us, is called fate, but if we consider its purposiveness in the course of the world as the profound wisdom of a higher cause directed to the objective final end of the human race and predetermining this course of the world, it is called providence.^[151]

Kant's political thought can be summarized as republican government and international organization: "In more characteristically Kantian terms, it is doctrine of the state based upon the law (Rechtsstaat) and of eternal peace. Indeed, in each of these formulations, both terms express the same idea: that of legal constitution or of 'peace through law.'"^[152] "Kant's political philosophy, being essentially a legal doctrine, rejects by definition the opposition between moral education and the play of passions as alternate foundations for social life. The state is defined as the union of men under law. The state rightly so called is constituted by laws which are necessary a priori because they flow from the very concept of law. A regime can be judged by no other criteria nor be assigned any other functions, than those proper to the lawful order as such."^[153]

He opposed "democracy", which at his time meant direct democracy, believing that majority rule posed a threat to individual liberty. He stated, "democracy in the strict sense of the word is necessarily a despotism because it establishes an executive power in which all decide for and, if need be, against one (who thus does not agree), so that all, who are nevertheless not all, decide; and this is a contradiction of the general will with itself and with freedom."^[154] As with most writers at the time, he distinguished three forms of government—namely, democracy, aristocracy, and monarchy—with mixed government as the most ideal form of it.

He believed in republican ideals and forms of governance, and rule of law brought on by them.

Although Kant published this as a "popular piece", Mary J. Gregor points out that two years later, in The Metaphysics of Morals, Kant claims to demonstrate systematically that "establishing universal and lasting peace constitutes not merely a part of the doctrine of right, but rather the entire final end of the doctrine of right within the limits of mere reason".^[155][156]

The Doctrine of Right, published in 1797, contains Kant's most mature and systematic contribution to political philosophy. It addresses duties according to law, which are "concerned only with protecting the external freedom of individuals" and indifferent to incentives. (Although we do have a moral duty "to limit ourselves to actions that are right, that duty is not part of [right] itself".)^[145] Its basic political idea is that "each person's entitlement to be his or her own master is only consistent with the entitlements of others if public legal institutions are in place".^[157]

Religious writings

Starting in the twentieth century, commentators have tended to see Kant as having a strained relationship with religion, although in the nineteenth century this had not been the prevalent view. Karl Leonhard Reinhold, whose letters helped make Kant famous, wrote: "I believe that I may infer without reservation that the interest of religion, and of Christianity in particular, accords completely with the result of the Critique of Reason."^[158] According to Johann Schultz, who wrote one of the first commentaries on Kant: "And does not this system itself cohere most splendidly with the Christian religion? Do not the divinity and beneficence of the latter become all the more evident?"^[159] The reason for these views was Kant's moral theology and the widespread belief that his philosophy was the great antithesis to Spinozism, which was widely seen as a form of sophisticated pantheism or even atheism. As Kant's philosophy disregarded the possibility of arguing for God through pure reason alone, for the same reasons it also disregarded the possibility of arguing against God through pure reason alone.

Kant articulates his strongest criticisms of the organization and practices of religious organizations to those that encourage what he sees as a religion of counterfeit service to God.^[160] Among the major targets of his criticism are external ritual, superstition, and a hierarchical church order. He sees these as efforts to make oneself pleasing to God in ways other than conscientious adherence to the principle of moral rightness in choosing and acting upon one's maxims. Kant's criticisms on these matters, along with his rejection of certain theoretical proofs for the existence of God that were grounded in pure reason (particularly the ontological argument) and his philosophical commentary on some Christian doctrines, have resulted in interpretations that see Kant as hostile to religion in general and to Christianity in particular.^[161] Other interpreters, nevertheless, consider that Kant was trying to mark off defensible from indefensible Christian belief.^[162]

Regarding Kant's conception of religion, some critics have argued that he was sympathetic to deism.^[163] Other critics have argued that Kant's moral conception moves from deism to theism (as moral theism), for example, Allen W. Wood^[164] and Merold Westphal.^[165] As for Kant's book Religion within the Bounds of Mere Reason, it was emphasized that Kant reduced religiosity to rationality, religion to morality, and Christianity to ethics.^[166] However, many interpreters, including Allen W. Wood^[167] and Lawrence Pasternack,^[168] now agree with Stephen Palmquist's claim that a better way of reading Kant's Religion is to see him as raising morality to the status of religion.^[169]

Aesthetics

Immanuel Kant

Kant discusses the subjective nature of aesthetic qualities and experiences in Observations on the Feeling of the Beautiful and Sublime (1764). Kant's contribution to aesthetic theory is developed in the Critique of the Power of Judgment (1790), where he investigates the possibility and logical status of "judgments of taste". In the "Critique of Aesthetic Judgment", the first major division of the Critique of the Power of Judgment, Kant used the term "aesthetic" in a manner that differs from its modern sense.^[170] In the Critique of Pure Reason, to note essential differences between judgments of taste, moral judgments, and scientific judgments, Kant abandoned the term "aesthetic" as "designating the critique of taste", noting that judgments of taste could never be "directed" by "laws a priori".^[171]

After A. G. Baumgarten, who wrote Aesthetica (1750–58),^{[lower-alpha 6]} Kant was one of the first philosophers to develop and integrate aesthetic theory into a unified and comprehensive philosophical system, utilizing ideas that played an integral role throughout his philosophy.^[172]

In the chapter "Analytic of the Beautiful" in the Critique of the Power of Judgment, Kant states that beauty is not a property of an artwork or natural phenomenon, but is instead consciousness of the pleasure that attends the 'free play' of the imagination and the understanding. Even though it appears that we are using reason to decide what is beautiful, the judgment is not a cognitive judgment,^{[lower-alpha 7]} "and is consequently not logical, but aesthetical".^[173]

A pure judgement of taste is subjective since it refers to the emotional response of the subject and is based upon nothing but esteem for an object itself: it is a disinterested pleasure, and we feel that pure judgements of taste (i.e., judgements of beauty), lay claim to universal validity.^[174] This universal validity is not derived from a determinate concept of beauty but from common sense.^[175] Kant also believed that a judgement of taste shares characteristics engaged in a moral judgement: both are disinterested, and we hold them to be universal.

In the chapter "Analytic of the Sublime" Kant identifies the sublime as an aesthetic quality that, like beauty, is subjective, but unlike beauty refers to an indeterminate relationship between the faculties of the imagination and of reason, and shares the character of moral judgments in the use of reason. The feeling of the sublime, divided into two distinct modes (the mathematical and the dynamical sublime), describes two subjective moments that concern the relationship of the faculty of the imagination to reason.

Some commentators^[176] argue that Kant's critical philosophy contains a third kind of the sublime, the moral sublime, which is the aesthetic response to the moral law or a representation, and a development of the "noble" sublime in Kant's theory of 1764.

The mathematical sublime results from the failure of the imagination to comprehend natural objects that appear boundless and formless, or appear "absolutely great".^[177] This imaginative failure is then recuperated through the pleasure taken in reason's assertion of the concept of infinity. In this move the faculty of reason proves itself superior to our fallible sensible self.^[178] In the dynamical sublime, there is the sense of annihilation of the sensible self as the imagination tries to comprehend a vast might. This power of nature threatens us but through the resistance of reason to such sensible annihilation, the subject feels a pleasure and a sense of the human moral vocation. This appreciation of moral feeling through exposure to the sublime helps to develop moral character.

Kant developed a theory of humor^[179] that has been interpreted as an "incongruity" theory. He illustrated his theory of humor by telling three narrative jokes in the Critique of Judgment. He thought that the physiological impact of humor is akin to that of music.^[180]

Kant developed a distinction between an object of art as a material value subject to the conventions of society and the transcendental condition of the judgment of taste as a "refined" value in his Idea for a Universal History with a Cosmopolitan Aim (1784). In the Fourth and Fifth Theses of that work he identified all art as the "fruits of unsociableness" due to men's "antagonism in society"^[181] and, in the Seventh Thesis, asserted that while such material property is indicative of a civilized state, only the ideal of morality and the universalization of refined value through the improvement of the mind "belongs to culture".^[182]

Anthropology

5 DM 1974 D silver coin commemorating the 250th birthday of Immanuel Kant in Königsberg

Kant lectured on anthropology, the study of human nature, for twenty-three years.^[183] His Anthropology from a Pragmatic Point of View was published in 1798. Transcripts of Kant's lectures on anthropology were published for the first time in 1997 in German.^[184]

Kant was among the first people of his time to introduce anthropology as an intellectual area of study, long before the field gained popularity, and his texts are considered to have advanced the field. His point of view was to influence the works of later philosophers such as Martin Heidegger and Paul Ricoeur.^[185]

Kant was also the first to suggest using a dimensionality approach to human diversity. He analyzed the nature of the Hippocrates-Galen four temperaments and plotted in two dimensions "what belongs to a human being's faculty of desire": "his natural aptitude or natural predisposition" and "his temperament or sensibility".^[186] Cholerics were described as emotional and energetic, phlegmatics as balanced and weak, sanguines as balanced and energetic, and melancholics as emotional and weak. These two dimensions reappeared in all subsequent models of temperament and personality traits.

Kant viewed anthropology in two broad categories: (1) the physiological approach, which he referred to as "what nature makes of the human being"; and (2) the pragmatic approach, which explores the things that a human "can and should make of himself".^[187]

Racism

Kant Mixing Mustard, drawn by Carl Friedrich Hagemann, 1801

Kant's theory of race and his prejudicial beliefs are among the most contentious areas of recent Kant scholarship.^{[188][189][190]} While few, if any, dispute the overt racism and chauvinism present in his work, a more contested question is the degree to which it degrades or invalidates his other contributions. His most severe critics assert that Kant intentionally manipulated science to support chattel slavery and discrimination.^{[191][192][188]} Others acknowledge that he lived in an era of immature science, with many erroneous beliefs, some racist, all appearing decades before evolution, molecular genetics, and other sciences that today are taken for granted.^{[188][189][193][194]}

Kant was one of the most notable Enlightenment thinkers to defend racism. Philosopher Charles W. Mills is unequivocal: "Kant is also seen as one of the central figures in the birth of modern 'scientific' racism. Whereas other contributors to early racial thought like Carolus Linnaeus and Johann Friedrich Blumenbach had offered only 'empirical' (scare-quotes necessary!) observation, Kant produced a full-blown theory of race."^[195]

Using the four temperaments of ancient Greece, Kant proposed a hierarchy of racial categories including white Europeans, black Africans, and red Native Americans.^[196] Although he was a proponent of scientific racism for much of his career, Kant's views on race changed significantly in the last decade of his life, and he ultimately rejected racial hierarchies and European colonialism in Perpetual Peace: A Philosophical Sketch (1795).^{[190][197][196][lower-alpha 8]}

Kant was an opponent of miscegenation, believing that whites would be "degraded" and that "fusing of races" is undesirable, for "not every race adopts the morals and customs of the Europeans." He states that "instead of assimilation, which was intended by the melting together of the various races, nature has here made a law of just the opposite."^[200]

Kant was also an anti-Semite, believing that Jews were incapable of transcending material forces, which a moral order required. In this way, Jews are presented as the opposite of autonomous, rational Christians, and therefore incapable of being incorporated into an ethical Christian society. In his "Anthropology", Kant called the Jews "a nation of cheaters" and portrayed them as "a group that has followed not the path of transcendental freedom but that of enslavement to the material world".^[201]

Charles W. Mills wrote that Kant has been "sanitized for public consumption", his racist works conveniently ignored.^[202] Robert Bernasconi stated that Kant "supplied the first scientific definition of race". Emmanuel Chukwudi Eze is credited with bringing Kant's contributions to racism to light in the 1990s among Western philosophers, who he believed often glossed over this part of his life and works.^[203]

Pauline Kleingeld argues that, while Kant "did defend a racial hierarchy until at least the end of the 1780s", his views on race changed significantly in works published in the last decade of his life. In particular, she argues that Kant rejected past views related to racial hierarchies and the diminished rights or moral status of non-whites in Perpetual Peace (1795). This work also saw him providing extended arguments against European colonialism, which he claimed was morally unjust and incompatible with the equal rights held by indigenous populations. Kleingeld argues that this shift in Kant's views later in life has often been forgotten or ignored in the literature on Kant's racist anthropology, and that the shift suggests a belated recognition of the fact that racial hierarchy was incompatible with a universalized moral framework.^[190]

While Kant's racist rhetoric is indicative of the state of scholarship and science during the 18th century, German philosopher Daniel-Pascal Zorn explains the risk of taking period quotations out of context. Many of Kant's most outrageous quotations are from a series of articles from 1777–1788, a public exchange among Kant, Herder, natural scientist Georg Forster, and other scholars prominent in that period.^{[204][205][206]} Kant asserts that all races of humankind are of the same species, challenging the position of Forster and others that the races were distinct species. While his commentary is clearly biased at times, certain extreme statements were patterned specifically to paraphrase or counter Forster and other authors.^[188][189] By considering the full arc of Kant's scholarship, Zorn notes the progression in both his philosophical and his anthropological works, "with which he argues, against the zeitgeist, for the unity of humanity".^[189]

Historical influence

During his own life, much critical attention was paid to Kant's thought. He influenced Reinhold, Fichte, Schelling, Hegel, and Novalis during the 1780s and 1790s.

Statue of Immanuel Kant in Kaliningrad (Königsberg), Russia. Replica by Harald Haacke of the original by Christian Daniel Rauch lost in 1945.

Samuel Taylor Coleridge was greatly influenced by Kant and helped to spread awareness of him, and of German Idealism generally, in the UK and the US. In his Biographia Literaria (1817), he credits Kant's ideas in coming to believe that the mind is not a passive, but an active agent in the apprehension of reality.

Hegel was one of Kant's first major critics. In Hegel's view the entire project of setting a "transcendental subject" (i.e., human consciousness) apart from the living individual as well as from nature, history, and society was fundamentally flawed,^[213] although parts of that very project could be put to good use in a new direction. Similar concerns motivated Hegel's criticisms of Kant's concept of moral autonomy, to which Hegel opposed an ethic focused on the "ethical life" of the community.^{[lower-alpha 10]} In a sense, Hegel's notion of "ethical life" is meant to subsume, rather than replace, Kantian ethics. And Hegel can be seen as trying to defend Kant's idea of freedom as going beyond finite "desires", by means of reason. Thus, in contrast to later critics like Nietzsche or Russell, Hegel shares some of Kant's concerns.^{[lower-alpha 11]}

Kant's thinking on religion was used in Britain by philosophers such as Thomas Carlyle^[214] to challenge the nineteenth-century decline in religious faith. British Catholic writers, notably G. K. Chesterton and Hilaire Belloc, followed this approach. Criticisms of Kant were common in the realist views of the new positivism at that time.

Arthur Schopenhauer was strongly influenced by Kant's transcendental idealism. He, like G. E. Schulze, Jacobi, and Fichte before him, was critical of Kant's theory of the thing-in-itself. Things-in-themselves, they argued, are neither the cause of what we observe, nor are they completely beyond our access. Ever since the Critique of Pure Reason, philosophers have been critical of Kant's theory of the thing-in-itself. Many have argued that, if such a thing exists beyond experience, then one cannot posit that it affects us causally, since that would entail stretching the category "causality" beyond the realm of experience.^{[lower-alpha 12]}

With the success and wide influence of Hegel's writings, Kant's own influence began to wane, but a re-examination of his ideas began in Germany in 1865 with the publication of Kant und die Epigonen by Otto Liebmann, whose motto was "Back to Kant". There proceeded an important revival of Kant's theoretical philosophy, known as Neo-Kantianism.

Weimar Republic stamp honoring Kant, 1926

Kant's notion of "critique" has been more broadly influential. The early German Romantics, especially Friedrich Schlegel in his "Athenaeum Fragments", used Kant's reflexive conception of criticism in their Romantic theory of poetry.^[215] Also in aesthetics, Clement Greenberg, in his classic essay "Modernist Painting", uses Kantian criticism, what Greenberg refers to as "immanent criticism", to justify the aims of abstract painting, a movement Greenberg saw as aware of the key limitation—flatness—that makes up the medium of painting.^[216]

French philosopher Michel Foucault was also greatly influenced by Kant's notion of "critique" and wrote several pieces on Kant for a re-thinking of the Enlightenment as a form of "critical thought". He went so far as to classify his own philosophy as a "critical history of modernity, rooted in Kant".^[217]

Kant believed that mathematical truths were forms of synthetic a priori knowledge, which means they are necessary and universal, yet known through the a priori intuition of space and time, as transcendental preconditions of experience.^[218] Kant's often brief remarks about mathematics influenced the mathematical school known as intuitionism, a movement in philosophy of mathematics opposed to Hilbert's formalism, and Frege and Bertrand Russell's logicism.^{[lower-alpha 13]}

Influence on modern thinkers

West German postage stamp, 1974, commemorating the 250th anniversary of Kant's birth

With his Perpetual Peace, Kant is considered to have foreshadowed many of the ideas that have come to form the democratic peace theory, one of the main controversies in political science.^[219] More concretely, Constructivist theorist Alexander Wendt proposed that the anarchy of the international system could evolve from the 'brutish' Hobbesian anarchy understood by Realist theorists, through Lockean anarchy, and ultimately a Kantian anarchy in which states would see their self-interests as inextricably linked to the well being of other states, thus transforming international politics into a far more peaceful form.^[220]

Prominent recent Kantians include the British philosophers P. F. Strawson,^{[lower-alpha 14]} Onora O'Neill,^[221] and Quassim Cassam,^[222] and the American philosophers Wilfrid Sellars^[223] and Christine Korsgaard.^{[lower-alpha 15]} Due to the influence of Strawson and Sellars, among others, there has been a renewed interest in Kant's view of the mind. Central to many debates in philosophy of psychology and cognitive science is Kant's conception of the unity of consciousness.^{[lower-alpha 16]}

Jürgen Habermas and John Rawls are two significant political and moral philosophers whose work is strongly influenced by Kant's moral philosophy.^{[lower-alpha 17]} They have argued against relativism,^[224] supporting the Kantian view that universality is essential to any viable moral philosophy.

Mou Zongsan's study of Kant has been cited as a highly crucial part in the development of Mou's personal philosophy, namely New Confucianism. Widely regarded as the most influential Kant scholar in China, Mou's rigorous critique of Kant's philosophy—having translated all three of Kant's critiques—served as an ardent attempt to reconcile Chinese and Western philosophy whilst increasing pressure to westernize in China.^[225][226]

East German commemorative coin honoring Kant, 1974

Kant's influence has also extended to the social, behavioral, and physical sciences—as in the sociology of Max Weber, the psychology of Jean Piaget and Carl Gustav Jung,^[227][228] and the linguistics of Noam Chomsky. Kant's work on mathematics and synthetic a priori knowledge is also cited by theoretical physicist Albert Einstein as an early influence on his intellectual development, though one which he later criticized and rejected.^[229] In recent years, there has also been renewed interest in Kant's theory of mind from the point of view of formal logic and computer science.^[230]

Because of the thoroughness of Kant's paradigm shift, his influence extends well beyond this to thinkers who neither specifically refer to his work nor use his terminology.

List of major works

Abbreviations used in body of article are boldface in brackets. Unless otherwise noted, pagination is to the critical Akademie edition, which can be found in the margins of the Cambridge translations.

• 1749: Thoughts on the True Estimation of Living Forces (Gedanken von der wahren Schätzung der lebendigen Kräfte)
• 1755: Universal Natural History and Theory of the Heavens [UNH] (Allgemeine Naturgeschichte und Theorie des Himmels)
• 1755: Brief Outline of Certain Meditations on Fire (Meditationum quarundam de igne succinta delineatio (master's thesis under Johann Gottfried Teske))^{[231][232][233][234]}
• 1755: A New Elucidation of the First Principles of Metaphysical Cognition (Principiorum primorum cognitionis metaphysicae nova dilucidatio (doctoral thesis))^{[235][lower-alpha 18]}
• 1756: The Use in Natural Philosophy of Metaphysics Combined with Geometry, Part I: Physical Monadology [PM] (Metaphysicae cum geometrica iunctae usus in philosophia naturali, cuius specimen I. continet monadologiam physicam, abbreviated as Monadologia Physica (thesis as a prerequisite of associate professorship))^[236]
• 1762: The False Subtlety of the Four Syllogistic Figures (Die falsche Spitzfindigkeit der vier syllogistischen Figuren)
• 1763: The Only Possible Argument in Support of a Demonstration of the Existence of God (Der einzig mögliche Beweisgrund zu einer Demonstration des Daseins Gottes)
• 1763: Attempt to Introduce the Concept of Negative Magnitudes into Philosophy [NQ] (Versuch den Begriff der negativen Größen in die Weltweisheit einzuführen)
• 1764: Observations on the Feeling of the Beautiful and Sublime [OFBS] (Beobachtungen über das Gefühl des Schönen und Erhabenen)
• 1764: Essay on the Illness of the Head (Über die Krankheit des Kopfes)
• 1764: Inquiry Concerning the Distinctness of the Principles of Natural Theology and Morality (the Prize Essay) [PNTM] (Untersuchungen über die Deutlichkeit der Grundsätze der natürlichen Theologie und der Moral)
• 1766: Dreams of a Spirit-Seer [DSS] (Träume eines Geistersehers)^[237]
• 1768: On the Ultimate Ground of the Differentiation of Regions in Space [1768] (Von dem ersten Grunde des Unterschiedes der Gegenden im Raume)^[238]
• 1770: Dissertation on the Form and Principles of the Sensible and the Intelligible World [ID] (De mundi sensibilis atque intelligibilis forma et principiis [doctoral thesis])^{[239][240][241]}
• 1775: On the Different Races of Man (Über die verschiedenen Rassen der Menschen)
• 1781: First edition of the Critique of Pure Reason [CPuR A]^[242] (Kritik der reinen Vernunft)^[243]
• 1783: Prolegomena to Any Future Metaphysics [PFM] (Prolegomena zu einer jeden künftigen Metaphysik)
• 1784: "An Answer to the Question: What Is Enlightenment?" [WE?] ("Beantwortung der Frage: Was ist Aufklärung?")^[244]
• 1784: "Idea for a Universal History with a Cosmopolitan Purpose" [UH] ("Idee zu einer allgemeinen Geschichte in weltbürgerlicher Absicht")
• 1785: "Determination of the Concept of a Human Race" [DCHR] (Bestimmung des Begriffs einer Menschenrace)
• 1785: Groundwork of the Metaphysics of Morals [G] (Grundlegung zur Metaphysik der Sitten)
• 1786: Metaphysical Foundations of Natural Science [MFNS] (Metaphysische Anfangsgründe der Naturwissenschaft)
• 1786: "What does it mean to orient oneself in thinking?" [OT]("Was heißt: sich im Denken orientieren?")
• 1786: Conjectural Beginning of Human History [CB] (Mutmaßlicher Anfang der Menschengeschichte)
• 1787: Second edition of the Critique of Pure Reason [CPuR B]^[245] (Kritik der reinen Vernunft)^[246]
• 1788: Critique of Practical Reason [CPracR] (Kritik der praktischen Vernunft)^[247]
• 1790: Critique of Judgment [CPJ] (Kritik der Urteilskraft)^[248]
• 1793: Religion within the Bounds of Bare Reason [RBMR] (Die Religion innerhalb der Grenzen der bloßen Vernunft)^[44][249]
• 1793: On the Old Saw: That May be Right in Theory But It Won't Work in Practice [TP] (Über den Gemeinspruch: Das mag in der Theorie richtig sein, taugt aber nicht für die Praxis)
• 1795: Perpetual Peace: A Philosophical Sketch^[250] [PP] ("Zum ewigen Frieden")^[251]
• 1797: Metaphysics of Morals [MM] (Metaphysik der Sitten). First part is The Doctrine of Right, which has often been published separately as The Science of Right.
• 1798: Anthropology from a Pragmatic Point of View [APPV] (Anthropologie in pragmatischer Hinsicht)
• 1798: Conflict of Faculties [CF]^[252] (Der Streit der Fakultäten)^[253]
• 1800: Logic (Logik)
• 1803: On Pedagogy (Über Pädagogik)^[254]
• 1804: Opus Postumum [OP]
• 1817: Lectures on Philosophical Theology (Immanuel Kants Vorlesungen über die philosophische Religionslehre edited by K.H.L. Pölitz) [The English edition of A.W. Wood & G.M. Clark (Cornell, 1978) is based on Pölitz' second edition, 1830, of these lectures.]^{[lower-alpha 19]}

Collected works in German

Wilhelm Dilthey inaugurated the Academy edition (the Akademie-Ausgabe abbreviated as AA or Ak) of Kant's writings (Gesammelte Schriften, Königlich-Preußische Akademie der Wissenschaften, Berlin, 1902–38) in 1895,^[255] and served as its first editor. The volumes are grouped into four sections:

• I. Kant's published writings (vols. 1–9),
• II. Kant's correspondence (vols. 10–13),
• III. Kant's literary remains, or Nachlass (vols. 14–23), and
• IV. Student notes from Kant's lectures (vols. 24–29).

An electronic version is also available: Elektronische Edition der Gesammelten Werke Immanuel Kants (vols. 1–23).

Citations

Works cited