Kant, Immanuel

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Immanuel Kant

Immanuel Kant
Full name	Immanuel Kant
Born	22 April 1724 Königsberg, Prussia (Now Kaliningrad, Russia)
Died	12 February 1804(1804-02-12) (aged 79) Königsberg, Prussia
Era	18th-century philosophy
Region	Western Philosophy
School	Kantianism, enlightenment philosophy
Main interests	Epistemology, Metaphysics, Ethics, Logic
Notable ideas	Categorical imperative, Transcendental Idealism, Synthetic a priori, Noumenon, Sapere aude, Nebular hypothesis
Influenced by Wolff, Baumgarten, Tetens, Hutcheson, Empiricus, Montaigne, Hume, Descartes, Malebranche, Spinoza, Leibniz, Locke, Berkeley, Rousseau, Newton, Emanuel Swedenborg, Shaftesbury
Influenced Virtually all later Western Philosophy including: Fichte, Schelling, Hegel, Schopenhauer, Nietzsche, Peirce, Husserl, Heidegger, Sartre, Cassirer, Habermas, Rawls, Chomsky, Nozick, Popper, Kierkegaard, Jung, Searle, Foucault, Arendt, Gentile, Jaspers, Bergson, Ørsted, Ayer, Emerson, Weininger, Strawson, Strauss, Putnam, McDowell, Durkheim
Signature

Part of a series on
Immanuel Kant
Kantianism and deontological ethics
Transcendental idealism Critical philosophy Sapere aude · Schema A priori ... a posteriori Analytic-synthetic distinction Noumenon · Categories Categorical imperative Hypothetical imperative "Kingdom of Ends" Political philosophy
Major works
Critique of Pure Reason Prolegomena What Is Enlightenment? Groundwork of the Metaphysic of Morals Critique of Practical Reason Critique of Judgement Religion within the Bounds of Bare Reason
People
George Berkeley René Descartes  · Fichte Friedrich Heinrich Jacobi G.W.F. Hegel · David Hume Arthur Schopenhauer Baruch Spinoza · African Spir Johannes Tetens
Related topics
German idealism Schopenhauer's criticism Neo-Kantianism
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Immanuel Kant (German pronunciation: [ɪˈmaːnu̯eːl ˈkant]) (22 April 1724 – 12 February 1804) was an 18th-century German philosopher from the Prussian city of Königsberg. Kant was the last influential philosopher of modern Europe in the classic sequence of the theory of knowledge during the Enlightenment beginning with thinkers John Locke, George Berkeley, and David Hume.^[1]

Kant created a new perspective in philosophy which had widespread influences on philosophy continuing through to the 21st century. He published important works on epistemology, as well as works relevant to religion, law, and history. One of his most prominent works is the Critique of Pure Reason, an investigation into the limitations and structure of reason itself. It encompasses an attack on traditional metaphysics and epistemology, and highlights Kant's own contribution to these areas. The other main works of his maturity are the Critique of Practical Reason, which concentrates on ethics, and the Critique of Judgment, which investigates aesthetics and teleology.

Kant suggested that metaphysics can be reformed through epistemology.^[2] He suggested that by understanding the sources and limits of human knowledge we can ask fruitful metaphysical questions. He questioned whether or not an object can be known to have certain properties prior to the experience of that object. He concluded that all objects about which the mind can think must conform to its manner of thought. Therefore if the mind can think only in terms of causality – which he concluded that it does – then we can know prior to experiencing them that all objects we experience must either be a cause or an effect. However, it follows from this that it is possible that there are objects of such nature which the mind cannot think, and so the principle of causality, for instance, cannot be applied outside of experience: hence we cannot know, for example, whether the world always existed or if it had a cause. And so the grand questions of speculative metaphysics cannot be answered by the human mind, but the sciences are firmly grounded in laws of the mind.^[3]

Kant believed himself to be creating a compromise between the empiricists and the rationalists. The empiricists believed that knowledge is acquired through experience alone, but the rationalists maintained that such knowledge is open to Cartesian doubt and that reason alone provides us with knowledge. Kant argues, however, that using reason without applying it to experience will only lead to illusions, while experience will be purely subjective without first being subsumed under pure reason.

Kant’s thought was very influential in Germany during his lifetime, moving philosophy beyond the debate between the rationalists and empiricists. The philosophers Fichte, Schelling, Hegel and Schopenhauer each saw themselves as correcting and expanding the Kantian system, thus bringing about various forms of German idealism. Kant continues to be a major influence on philosophy, influencing both analytic and continental philosophy.

[edit] Biography

Immanuel Kant was born in 1724 in Königsberg, the capital of Prussia at that time, today the city of Kaliningrad in the Russian exclave of Kaliningrad Oblast. He was the fourth of eleven children (four of them reached adulthood). Baptized 'Emanuel', he changed his name to 'Immanuel'^[4] after learning Hebrew. In his entire life, he never traveled more than ten miles from Königsberg.^[5] His father, Johann Georg Kant (1682–1746), was a German harnessmaker from Memel, at the time Prussia's most northeastern city (now Klaipėda, Lithuania). His mother, Regina Dorothea Reuter (1697–1737), was born in Nuremberg.^[6] Kant's grandfather had emigrated from Scotland to East Prussia, and his father still spelled their family name "Cant."^[7] In his youth, Kant was a solid, albeit unspectacular, student. He was reared in a Pietist household that stressed intense religious devotion, personal humility, and a literal interpretation of the Bible. Consequently, Kant received a stern education – strict, punitive, and disciplinary – that preferred Latin and religious instruction over mathematics and science.^[8] Of the common myths concerning Kant's personal mannerisms are enumerated, explained, and refuted in Goldthwait's introduction to his translation of Observations on the Feeling of the Beautiful and Sublime.^[9] It is often held that Kant lived a very strict and predictable life, leading to the oft-repeated story that neighbors would set their clocks by his daily walks. He never married, but didn't seem to lack a rewarding social life - he was a popular teacher and a modestly successful author even before starting on his major philosophical works.

[edit] The young scholar

Kant showed a great aptitude to study at an early age. He was first sent to Collegium Fredericianum and then enrolled at the University of Königsberg (where he would spend his entire career) in 1740, at the age of 16.^[10] He studied the philosophy of Leibniz and Wolff under Martin Knutzen, a rationalist who was also familiar with developments in British philosophy and science and who introduced Kant to the new mathematical physics of Newton. Knutzen dissuaded Kant from the theory of pre-established harmony, which he regarded as "the pillow for the lazy mind". He also dissuaded the young scholar from idealism, which was negatively regarded by most philosophers in the 18th century (The theory of transcendental idealism that Kant developed in the "Critique of Pure Reason" is not traditional idealism, i.e. the idea that reality is purely mental. In fact, Kant produced arguments against traditional idealism in the second part of the "Critique of Pure Reason"). His father's stroke and subsequent death in 1746 interrupted his studies. Kant became a private tutor in the smaller towns surrounding Königsberg, but continued his scholarly research. 1749 saw the publication of his first philosophical work, Thoughts on the True Estimation of Living Forces.

Kant is best known for his transcendental idealist philosophy that time and space are not materially real but merely the ideal a priori condition of our internal intuition. Also, he made an important astronomical discovery, namely the discovery of the retardation of the rotation of the Earth, for which he won the Berlin Academy Prize in 1754. Even more importantly, from this Kant concluded that time is not a thing in itself determined from experience, objects, motion, and change, but rather an unavoidable framework of the human mind that preconditions possible experience.^{[citation needed]}

According to Lord Kelvin:

Kant pointed out in the middle of last century, what had not previously been discovered by mathematicians or physical astronomers, that the frictional resistance against tidal currents on the earth's surface must cause a diminution of the earth's rotational speed. This immense discovery in Natural Philosophy seems to have attracted little attention,--indeed to have passed quite unnoticed, --among mathematicians, and astronomers, and naturalists, until about 1840, when the doctrine of energy began to be taken to heart.

—Lord Kelvin, physicist, 1897

He became a university lecturer in 1755. The subject on which he lectured was "Metaphysics"; the course textbook was written by A.G. Baumgarten.

According to Thomas Huxley:

"The sort of geological speculation to which I am now referring (geological aetiology, in short) was created as a science by that famous philosopher, Immanuel Kant, when, in 1775 [1755], he wrote his General Natural History and Theory of the Celestial Bodies; or, an Attempt to Account for the Constitutional and Mechanical Origin of the Universe, upon Newtonian Principles." --

—Thomas H. Huxley, 1869

In the General History of Nature and Theory of the Heavens (Allgemeine Naturgeschichte und Theorie des Himmels) (1755), Kant laid out the Nebular hypothesis, in which he deduced that the Solar System formed from a large cloud of gas, a nebula. He thus attempted to explain the order of the solar system, seen previously by Newton as being imposed from the beginning by God. Kant also correctly deduced that the Milky Way was a large disk of stars, which he theorized also formed from a (much larger) spinning cloud of gas. He further suggested the possibility that other nebulae might also be similarly large and distant disks of stars. These postulations opened new horizons for astronomy: for the first time extending astronomy beyond the solar system to galactic and extragalactic realms.^[11]

From this point 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. In 1764, Kant wrote Observations on the Feeling of the Beautiful and Sublime and then 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 1770, at the age of 45, Kant was finally appointed Professor of Logic and Metaphysics at the University of Königsberg. Kant wrote his Inaugural Dissertation in defence of this appointment. 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. Not to observe this distinction would mean to commit the error of subreption, and, as he says in the last chapter of the dissertation, only in avoidance of this error will metaphysics flourish.

The issue that vexed Kant was central to what twentieth century scholars termed "the philosophy of mind." The flowering of the natural sciences had led to an understanding of how data reaches the brain. Sunlight may fall upon a distant object, whereupon light is reflected from various parts of the object in a way that maps the surface features (color, texture, etc.) of the object. The light reaches the eye of a human observer, passes through the cornea, is focused by the lens upon the retina where it forms an image similar to that formed by light passing through a pinhole into a camera obscura. The retinal cells next send impulses through the optic nerve and thereafter they form a mapping in the brain of the visual features of the distant object. The interior mapping is not the exterior thing being mapped, and our belief that there is a meaningful relationship between the exterior object and the mapping in the brain depends on a chain of reasoning that is not fully grounded. But the uncertainty aroused by these considerations, the uncertainties raised by optical illusions, misperceptions, delusions, etc., are not the end of the problems.

Kant saw the mind could not function as an empty container that simply receives data from the outside. Something had to be giving order to the incoming data. Images of external objects have to be kept in the same sequence in which they were received. This ordering occurs through the mind's intuition of time. The same considerations apply to the mind's function of constituting space for ordering mappings of visual and tactile signals arriving via the already described chains of physical causation.

[edit] Early work

It is often held that Kant was a late bloomer, that he only became an important philosopher in his mid-50s 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.^[12]

[edit] The silent decade

At the age of 46, Kant was an established scholar and an increasingly influential philosopher. Much was expected of him. In response to a letter from his student, Markus Herz, Kant came to recognize that in the Inaugural Dissertation, he had failed to account for the relation and connection between our sensible and intellectual faculties, i.e., he needed to explain both how humans acquire data and how they process data—related but very different processes. He also credited David Hume with awakening him from "dogmatic slumber" (circa 1771).^[13] Kant did not publish any work in philosophy for the next eleven years.

Immanuel Kant

Kant spent his silent decade working on a solution to the problem mentioned above. Although fond of company and conversation with others, Kant isolated himself. He resisted friends' attempts to bring him out of his isolation. In 1778, in response to one of these offers by a former pupil, Kant wrote

"Any change makes me apprehensive, even if it offers the greatest promise of improving my condition, and I am persuaded by this natural instinct of mine that I must take heed if I wish that the threads which the Fates spin so thin and weak in my case to be spun to any length. My great thanks, to my well-wishers and friends, who think so kindly of me as to undertake my welfare, but at the same time a most humble request to protect me in my current condition from any disturbance."^[14]

When Kant emerged from his silence in 1781, the result was the Critique of Pure Reason. Although now uniformly recognized as one of the greatest works in the history of philosophy, this Critique was largely ignored upon its initial publication. The book was long, over 800 pages in the original German edition, and written in what some considered a convoluted style. It received few reviews, and these granted no significance to the work. Its density made it, as Johann Gottfried Herder put it in a letter to Johann Georg Hamann, a "tough nut to crack," obscured by "…all this heavy gossamer."^[15] Its reception stood in stark contrast to the praise Kant had received for earlier works such as his "Prize Essay" and other shorter works that precede the first Critique. These well-received and readable tracts include one on the earthquake in Lisbon which was so popular that it was sold by the page.^[16] Prior to the change in course documented in the first Critique, his books sold well, and by the time he published Observations On the Feeling of the Beautiful and the Sublime in 1764 he had become a popular author of some note.^[17] Kant was disappointed with the first Critique's reception. 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. He also encouraged his friend, Johann Schultz, to publish a brief commentary on the Critique of Pure Reason.

Kant's reputation gradually rose through the 1780s, sparked by a series of important works: the 1784 essay, "Answer to the Question: What is Enlightenment?"; 1785s 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 Reinhold began to publish a series of public letters on the Kantian philosophy. In these letters, Reinhold framed Kant's philosophy as a response to the central intellectual controversy of the era: the Pantheism Dispute. Friedrich Jacobi had accused the recently deceased G. E. Lessing (a distinguished dramatist and philosophical essayist) of Spinozism. Such a charge, tantamount to atheism, was vigorously denied by Lessing's friend Moses Mendelssohn, and a bitter public dispute arose among partisans. The controversy gradually escalated into a general debate over the values of the Enlightenment and the value of reason itself. 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.

[edit] Mature work

Kant published a second edition of the Critique of Pure Reason (Kritik der reinen Vernunft) 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 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, 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 1789 French Revolution.^[18] Kant then arranged to have all four pieces published as a book, routing it through the philosophy department at University of Jena to avoid the need for theological censorship.^{[citation needed]} Kant got the famous reprimand by the King,^[18] for this action of insubordination. 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.^{[citation needed]} Kant then published his response to the King's reprimand and explained himself, in the preface of The Conflict of the Faculties.^[18]

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 the Kantian philosophy. But despite his success, philosophical trends were moving in another direction. Many of Kant's most important disciples (including Reinhold, Beck and Fichte) transformed the Kantian position into increasingly radical forms of idealism. 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.^[19] It was one of his final acts expounding a stance on philosophical questions. In 1800, a student of Kant, named Gottlob Benjamin Jäsche, published a manual of logic for teachers called Logik, which he had prepared at the request of Kant. Jäsche prepared the Logik using a copy of a text book in logic by Georg Freidrich Meier entitled Auszug aus der Vernunftlehre, in which Kant had written copious notes and annotations. The Logik has been considered to be of fundamental importance to Kant's philosophy, and the understanding of it. For, the great nineteenth century logician Charles Sanders Peirce remarked, in an incomplete review of Thomas Kingsmill Abbott's English translation of the introduction to the Logik, that "Kant's whole philosophy turns upon his logic."^[20] 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."^[21] Kant's health, long poor, took a turn for the worse and he died at Königsberg on 12 February 1804 uttering "Genug" [enough] before expiring.^[22] His unfinished final work, the fragmentary Opus Postumum, was (as its title suggests) published posthumously.

Kant never concluded that one could form a coherent account of the universe and of human experience without grounding such an account in the "thing in itself". Many of those who followed him argued that since the "thing in itself" was unknowable its existence could not simply be assumed. Rather than arbitrarily switching to an account that was ungrounded in anything supposed to be the "real," as did the German Idealists, another group arose to ask how our (presumedly reliable) accounts of a coherent and rule-abiding universe were actually grounded. This new kind of philosophy became known as Phenomenology, and its preeminent spokesman was Edmund Husserl.

[edit] Philosophy

In Kant's essay "Answering the Question: What is Enlightenment?", Kant defined the Enlightenment as an age shaped by the Latin motto Sapere aude ("Dare to Know"). Kant maintained that one ought to think autonomously, free of the dictates of external authority. His work reconciled many of the differences between the rationalist and empiricist traditions of the 18th century. He had a decisive impact on the Romantic and German Idealist philosophies of the 19th century. His work has also been a starting point for many 20th century philosophers.

Kant asserted that, because of the limitations of argumentation in the absence of irrefutable evidence, no one could really know whether there is a God and an afterlife or not. For the sake of society and morality, Kant asserted, people are reasonably justified in believing in them, even though they could never know for sure whether they are real or not. He explained:

The sense of an enlightened approach and the critical method required that "If one cannot prove that a thing is, he may try to prove that it is not. And if he succeeds in doing neither (as often occurs), he may still ask whether it is in his interest to accept one or the other of the alternatives hypothetically, from the theoretical or the practical point of view. Hence the question no longer is as to whether perpetual peace is a real thing or not a real thing, or as to whether we may not be deceiving ourselves when we adopt the former alternative, but we must act on the supposition of its being real."^[24] The presupposition of God, soul, and freedom was then a practical concern, for "Morality, by itself, constitutes a system, but happiness does not, unless it is distributed in exact proportion to morality. This, however, is possible in an intelligible world only under a wise author and ruler. Reason compels us to admit such a ruler, together with life in such a world, which we must consider as future life, or else all moral laws are to be considered as idle dreams… ."^[25]

The two interconnected foundations of what Kant called his "critical philosophy" that created the "Copernican revolution" that he claimed to have wrought in philosophy were his epistemology of Transcendental Idealism and his moral philosophy of the autonomy of practical reason. These teachings placed the active, rational human subject at the center of the cognitive and moral worlds. With regard to knowledge, Kant argued that the rational order of the world as known by science could never be accounted for merely by the fortuitous accumulation of sense perceptions. It was instead the product of the rule-based activity of "synthesis." This activity consisted of conceptual unification and integration carried out by the mind through concepts or the "categories of the understanding" operating on the perceptual manifold within space and time, which are not concepts,^[26] but are forms of sensibility that are a priori necessary conditions for any possible experience. Thus the objective order of nature and the causal necessity that operates within it are dependent upon the mind. There is wide disagreement among Kant scholars on the correct interpretation of this train of thought. The 'two-world' interpretation regards Kant's position as a statement of epistemological limitation, that we are never able to transcend the bounds of our own mind, meaning that we cannot access the "thing-in-itself". Kant, however, also speaks of the thing in itself or transcendental object as a product of the (human) understanding as it attempts to conceive of objects in abstraction from the conditions of sensibility. Following this line of thought, some interpreters have argued that the thing in itself does not represent a separate ontological domain but simply a way of considering objects by means of the understanding alone – this is known as the two-aspect view. 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.

These ideas have largely framed or influenced all subsequent philosophical discussion and analysis. The specifics of Kant's account generated immediate and lasting controversy. Nevertheless, his theses – that the mind itself necessarily makes a constitutive contribution to its knowledge, that this contribution is transcendental rather than psychological, that philosophy involves self-critical activity, that morality is rooted in human freedom, and that to act autonomously is to act according to rational moral principles – have all had a lasting effect on subsequent philosophy.

[edit] Theory of perception

Kant defines his theory of perception in his influential 1781 work The Critique of Pure Reason, which has often been cited as the most significant volume of metaphysics and epistemology in modern philosophy. Kant maintains that our understanding of the external world had its foundations not merely in experience, but in both experience and a priori concepts, thus offering a non-empiricist critique of rationalist philosophy, which is what he and others referred to as his "Copernican revolution".^[27]

Firstly, Kant's distinction between analytic and synthetic propositions:

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."
2. Synthetic proposition: a proposition whose predicate concep