Immanuel Kant is one of the most influential philosophers in the history of

Welcome to our topic which is the German philosopher Immanuel Kant! Immanuel Kant is one of the most influential philosophers in the history of Western philosophy. His contributions to metaphysics, epistemology, ethics, and aesthetics have had a profound impact on almost every philosophical movement that followed him. This article focuses on his metaphysics and epistemology in one of his most important works, The Critique of Pure Reason. A large part of Kant’s work addresses the question “What can we know?” of the Rationalist philosophers and “How do we learn?” of the Empiricist philosophers. Kant took himself to have effected a “Copernican revolution” in philosophy, akin to Copernicus’ reversal of the age-old belief that the sun revolved around the earth. His beliefs continue to have a major influence on contemporary philosophy, especially the fields of metaphysics, epistemology, ethics, political theory, and aesthetics.

“All our knowledge begins with the senses, proceeds then to the understanding, and ends with reason. There is nothing higher than reason.” ~ Immanuel Kant

Intended learning outcomes

At the completion of this topic, you should be able to:

Explain the epistemological theory of Immanuel Kant;
Discuss his viewpoint on Copernican revolution of philosophy; and
Elaborate the Ethics and categorical imperative of Immanuel Kant.

Who is Immanuel Kant?

Immanuel Kant (1724-1804) was born into a family of financially struggling artisans in 1724, and he lived and worked his whole life in the cosmopolitan Baltic port city of Konigsberg, then part of Prussia. Though he never left his native province, he became an internationally famous philosopher within his own lifetime. Kant studied philosophy, physics, and mathematics at the University of Konigsberg, and taught at the same institution for the next 27 years. In 1792 his unorthodox views led King Friedrich Wilhelm II to ban him from teaching, to which he returned after the king’s death five years later. Kant published throughout his career, but is best known for the series of ground-breaking works he produced in his 50s and 60s. Though a bright and sociable man, he never married, and died at the age of 80.

Copernican revolution of Immanuel Kant

The major philosophical systems of his time, Rationalism and Empiricism, seemed to Immanuel Kant inadequate to explain the two major issues which he articulated in his famous statement:

“Two things fill the mind with ever new and increasing admiration and awe…the starry heavens above and the moral law within.”

On the one hand, the heavens as understood by science seemed to be ordered by deterministic laws while on the other, man was free.
For Kant, the problem was in reconciling these two seemingly irreconcilable problems.

It appeared to Kant, the direction that science was going was to incorporate all reality, including human behavior, into a mechanical model.

This would suggest that all events, being part of a unified mechanism, could be explained by cause and effect.
Pushing this method to its ultimate conclusion science would eventually have no need for such notions as freedom and God.

Kant was impressed by science. And it appeared to him was that its success lay in the fact that it functioned independently from either strict Empiricism or Rationalism.

Rationalism was based upon a mathematical model which emphasized the relationship between ideas and not necessarily the way things are in reality. Rationalism ultimately leads to dogmatism since its metaphysical speculations were not based upon experience.
Hume’s attack on causality made inductive inference, the very heart of science, problematic. Empiricism ultimately leads to skepticism.

Therefore, Immanuel Kant faced two major questions:

If the scientific method was applied to study all reality, notions of morality, freedom, and God were threatened by absorption into a mechanical universe.
How can scientific knowledge be justified, that is, have scientists sufficiently explained how they come to understand nature?

As it turns out, these two questions are related. In fact, Kant concluded that scientific knowledge is similar to metaphysical knowledge. Thus the justification or explanation of scientific thought on the one hand and metaphysical thought concerning freedom and morality on the other are the same.

Kant rescued metaphysics without attacking science. Both in science and in metaphysics our minds start with some given fact, which gives rise to a judgment within our reason.
“The genuine method of metaphysics is fundamentally the same kind which Newton introduced into natural science and which was there so fruitful.”
With this interpretation of scientific and moral thought, Kant provided a new function and life for philosophy. This new function was the critical appraisal of the capacity of human reason.

In pursuing this line of thinking, Kant achieved what he called his “Copernican revolution in philosophy.” Immanuel Kant in his Critique of Pure Reason (1787 edition) drew a parallel between the “Copernican revolution” and the epistemology of his new transcendental philosophy. Kant argues, that just as Copernicus moved from the supposition of heavenly bodies revolving around a stationary spectator to a moving spectator, so metaphysics, “proceeding precisely on the lines of Copernicus’ primary hypothesis”, should move from assuming that “knowledge must conform to objects” to the supposition that “objects must conform to our knowledge.”

Immanuel Kant and his Critical Philosophy

Kant agreed with Hume (and the empiricists) that knowledge starts with experience, but he disagreed with them in their concluding that experience is the source of all knowledge:

“…though our knowledge begins with experience, it does not follow that it all arises out of experience…” ~ Immanuel Kant

Kant further rejected Hume’s explanation that causality was simply a habit of mind connecting two events that we call cause and effect. Instead, Kant believed that we have knowledge about causality and that we get this knowledge not from sense experience but directly from the faculty of rational judgment and, therefore, this knowledge is called a priori.

What is a priori knowledge? It is knowledge that cannot be derived from experience.

For example, we know that every change has a cause, but we do not know this from experience because we have not experienced every change. Neither can experience tell us that events are necessary.
Hence, experience does not give us knowledge of the universality of proposition or the necessary connections. For this knowledge we rely on a priori judgments.

Synthetic a priori

Kant defines a judgment as an operation of thought whereby we connect a subject and predicate, where the predicate qualifies in some way the subject.

In analytical judgment, the predicate is already contained in the concept of the subject.

The judgment that all triangles have three sides is an analytical judgment.
Because the predicate is already implicit in the subject it offers us no new knowledge of the subject.
To deny an analytic judgment would involve a logical contradiction.

A synthetic judgment differs from the analytic in that its predicate is not contained in the subject. Thus in a synthetic judgment, the predicate adds something new to the subject.

Thus the statement, “The flower is pink” joins two independent concepts since pink is not implicit in flower.

Thus, all analytic judgments are a priori since our knowledge of such matters does not require experience. Furthermore, Kant continues, “necessity and strict universality are sure marks of a a priori knowledge.” Synthetic judgments are, for the most part, a posteriori, that is, they occur after an experience of observation.

But Kant takes it a step further by proposing the existence of the synthetic a priori. This was the judgment that Kant was most concerned about.

Consider the judgment that 7 + 5 = 12. This is a priori but also synthetic because it contains the marks of necessity and universality: 7 plus 5 necessarily equals 12 and it universally (always) equals 12.
Kant also offers a further illustration: “…that a straight line between two points is the shortest…,” is a synthetic proposition. For my concept of straight contains no notion of quantity, but only quality. The concept of shortest is thus wholly an addition, and it cannot be derived by any analysis from the concept of a straight line. Intuition must, therefore, lend its aid here, by means of which alone is this synthesis possible.”
His comment earlier about “…the moral law within,” a suggestion of the Natural Law, is an example of the synthetic a priori in metaphysics since it too implies necessity and universality.
Kant further suggests that “natural science contains within itself synthetic a priori judgments as principles.” Every statement of scientific law or theory exists as a synthetic a priori since it is marked by necessity and universality.

Thus, not only does metaphysics rely on the synthetic a priori, but also mathematics and science. If these judgments pose problems for metaphysics then they pose the same problems for science and mathematics. Thus, Kant figured that if he could explain the synthetic a priori he could justify both science and metaphysics.

The Structure of Rational Thought

Immanuel Kant says that “there are two sources of human knowledge, which perhaps spring from a common but to us unknown root, namely, sensibility and understanding.” Through the former objects are given to us; through the latter they are thought.

Knowledge is a cooperation between the thing known and the knower. Although I can distinguish myself as the knower from the object of my knowledge I can never truly know an object as it is.
My mind imposes a framework on the object of knowledge as I attempt to know the object. It is as though I were seeing the world through colored glasses never perceiving it as it really is.

What specifically is this framework that my mind brings to those things perceived through the senses? Kant’s response was there are Categories of Thought and Forms of Intuition.

Categories of Thought and Forms of Intuition

The mind attempts to synthesize a unity from the plurality of experience, which it receives from the senses.
The mind achieves this by imposing certain forms of intuition on these experiences.
We intuitively perceive things in space and time. Space and time are not immediately understood through experience and a thus known a priori.
There are other intuitive forms. When we impose quantity on experience we differentiate one or many. When we make a judgment of quality we make a positive (good) or negative (bad) statement. When we think of relation we think of cause and effect or the relationship of subject and predicate. Finally, when we think of modality we judge things as either possible or impossible.

The Self and the Unity of Experience

What makes it possible for us to have a unified grasp of the world? This type of knowledge involves sensation, imagination, memory, and the capacity of intuitive synthesis. Yet if each of these were a separate operation they could yield an incoherent picture of the world.
Kant reasoned that the fact that this is not the case indicates that there exists a unity of self.
1. He calls this single subject that accomplishes this unifying activity the “transcendental unity of apperception”—the self
2. He calls the self “transcendental” because we do not experience the self directly through experience. Thus the idea of self is a priori — a necessary condition to experience the world around us as a unified whole.
In the act of unifying all the elements of experience, we are conscious of our own unity so that our consciousness of a unified world of experience and our own self-consciousness occur simultaneously.
1. Our self-consciousness, however, is affected by the same faculties that affect our perception of external objects. I bring to the knowledge of myself the same apparatus and, therefore, impose upon myself as an object of knowledge the same “lenses” through which I see everything.
2. Just as I do not know things as they are apart from the perspective from which I see them, so also I do not know the nature of this “self” except that I am aware of the knowledge I have of the unity of experience.

Phenomenal and Noumenal Reality

It is clear that Kant’s epistemological system limits knowledge because our faculties of perception and our thinking imposes on the raw data of experience in such a way that we do not know if the things perceived are in fact the way they really are.
Kant concludes therefore that there are two realities:
1. Phenomenal Reality, that is, the world as we experience it, and
2. Noumenal Reality, that is, purely intelligible, or nonsensual reality.
When we experience a thing we perceive it through the lens of our a priori categories of thought. But what is a thing like when it is not being perceived? What is a thing-in-itself (Ding an sich)?
1. According to Kant, we cannot know a thing-in-itself since there is no such thing as nonsensual perception.
2. Consequently, human knowledge is fundamentally limited in its ability to know external reality.

Transcendental Ideas of Pure Reason as Regulative Concepts

Kant proposes that there are three regulative ideas that lead us beyond sense experience and which are necessary in our attempt to unify the plurality of our experiences. These ideas are: the self, cosmos, and God.
These ideas are transcendental because they do not correspond to any object of our direct experience.
1. Kant suggests that they are not the result of intuition, but pure reason.
2. Furthermore, they are prompted in the sense that we think of these ideas in our attempts to achieve a coherent synthesis of our experience.
Kant says that “the first [regulative] idea is the ‘I’ itself, viewed simply as thinking nature or soul…endeavoring to represent all determinations as existing in a single subject, all powers, so far as possible, as derived from a single fundamental being, and all appearances in space as completely different from actions of thought.”
Pure reason also tries to create a synthesis of many events in experience by forming the concept of the world or cosmos: “…the second regulative idea of merely speculative reason is the concept of the world in general…. The absolute totality of the series of conditions…an idea which can never be completely realized in the empirical employment of reason, but which yet serves as a rule that prescribes how we ought to proceed in dealing with such series…” The cosmological ideas are nothing but simply regulative principles, and are very far from positing…an actual totality of such series.
Finally, Kant sees the idea of God as an extension of reasons attempt to unify our experience beyond that of cosmos: “The third idea of pure reason, which contains a merely relative supposition of a being that is the sole and sufficient cause of all cosmological series, is the idea of God. We have not the slightest ground to assume in an absolute manner the object of this idea…. It becomes evident that the idea of such a being, like all speculative ideas, seems only to formulate the command of reason, that all connection in the world be viewed in accordance with the principles of a systematic unity—as if all such connection had its source in one single all-embracing being as the supreme and sufficient cause.”
Kant chooses the middle ground between skeptical empiricism and dogmatic rationalism. He agrees with the empiricists that we cannot know anything except what is presented to us through our senses. Nevertheless, ideas produced by reason alone such as self, cosmos, and God can help us synthesize coherence to our experiences. However, Kant makes it clear that he disagrees with the rationalists who believed that these ideas corresponded to objects: “…there is a great difference between something given to my reason as an object absolutely, or merely as an object in the idea. In the former case our concepts are employed to determine the object [transcendental]; in the latter case there is in fact only a scheme for which no object, not even a hypothetical one, is directly give, and which only enables us to represent to ourselves other objects in an indirect manner, namely in their systematic unity, by means of their relation to this idea. Thus, I say, that the concept of a highest intelligence is a mere idea.”

The Antinomies and the Limits of Reason

Because regulative ideas do not refer to any objective reality about which we can have knowledge, we must consider these ideas as being the products of our pure reason. As such we cannot bring to these ideas the a priori forms of time and space or the category of cause and effect since these are imposed by us only upon the sensible manifold.
Science is possible because all people, having the same structure of mind, will always and everywhere order the events of sense experience in the same way. But science is not possible for metaphysics [regulative ideas].
Kant states that we can have scientific knowledge of phenomena but not the noumenal realm. Our attempts at a “science” of metaphysics are doomed to failure. As proof of this Kant says that when we attempt to describe the self, cosmos, or God we inevitably fall into antinomies.
For Kant an antimony occurs when we can state opposite positions with equal force. Kant stated that there were four fundamental antinomies:
1. The world is limited in time and space or it is unlimited.
2. Every composite substance in the world is made up of simple parts, or that no composite thing in the world is made up of simple parts since there nowhere exists in the world anything simple
3. Besides causality in accordance with the laws of nature there is also another causality, that of freedom, or that there is no freedom since everything in the world takes place solely in accordance with the laws of nature.
4. There exists an absolutely necessary being as part of the world or as its cause, or an absolutely necessary being nowhere exits.
These disagreements occur in metaphysics because they are based on “nonsense”—that is, upon attempts to describe a reality about which we have, and can have, no sense experience.
Nevertheless, Kant believed that these antinomies had value. For example, we can think of a person in two different ways: as a phenomenon and as a noumenon.
1. As a phenomenon, a person can be studied scientifically as a being in space and time and in the context of cause and effect.
2. As a noumenon, what he is like beyond our sense perception of him cannot be known. The person as self exists at the limits of reason, an antinomy, and here freedom and therefore moral obligation can exist.

Practical Reason (Kantian Ethics)

Introduction

Immanuel Kant understood that the same reason involved in trying to understand the “starry heavens above” was also responsible for the “moral law within.”

Kant was also aware that the tendency of science was to increasingly include the entire cosmos, including human behavior, into a mechanistic view which would preclude human freedom:

“I could not…without palpable contradiction say of one and the same thing, for instance the human soul, that its will is free and yet is subject to natural necessity, that is not free.” ~ Immanuel Kant

Kant’s solution was to say that the person’s phenomenal self is subject to the cause and effect necessitated by a mechanistic universe. However, the person’s noumenal self possesses freedom. This freedom exist more as a result of the limits of reason than being an ontological reality of personhood:

“Our Critique limits speculative reason, it is indeed negative, but since it thereby removes an obstacle which stands in the way of the employment of practical reason, nay threatens to destroy it, it has in reality a positive and very important use.”

Kant therefore limits science to the phenomenal world and practical reason (ethics) to the noumenal world.

The Basis of Moral Knowledge

The task of moral philosophy is to discover how we are able to arrive at principles of behavior that are binding upon all people.

Kant did not believe that induction was an appropriate method for ascertaining these principles since that would simply tell us how people do behave not how they ought to behave.

For Kant the moral judgment, “we ought to tell the truth” is arrived at in the same way as the scientific statement, “every effect has a cause.”

In both cases, these judgments are derived from reason not experience.
Thus, just as theoretical reason brings the category of causality to the phenomenal world, practical reason brings the ought to the noumenal world.

Both in science and in moral philosophy we use concepts that go beyond any particular facts and like science, practical reason employs a priori Hence, he says:

“The basis of obligation must not be sought in human nature or in the circumstances of the world in which [humanity] is placed, but a priori simply in the concepts of reason.”

The qualities of universality and necessity are the marks of a priori judgments. This is further evidence to Kant that moral judgments are the result of practical reason a priori and not the Natural or Divine Law.

Morality and Rationality

As a rational being I not only ask, “What shall I do?” but also “What ought I to do?”
As I consider what I ought to do I recognize that this “ought” should be applicable to all rational persons.
Therefore, a morally good act is wither its principle can be applied to all rational beings and applied consistently.
Moral philosophy is the quest for these principles that apply to all rational beings and that lead to behavior that we call good.

“Good” Defined as the Good Will

Immanuel Kant believes that nothing is intrinsically good:

“Nothing can possibly be conceived in the world, or even out of it, which can be called ‘good,’ without qualification, except good will”

The essence of the morally good act is the disposition of the individual performing the act, not the act itself.

“The good will is good not because of what it causes or accomplishes, not because of its usefulness in the attainment of some set purpose, but alone because of the willing, that is to say, it is good of itself.”

An action cannot be judged as moral because the result of this action is determined to be a “good” such as the promotion of happiness for another. Rather, a moral action is good if it is performed for the sake of the moral law.

“For all these effects—even the promotion of the happiness of others—could have been also brought about by other causes, so that for this there would have been no need of the will of a rational being.”

The seat of moral worth is the will, and the good will is one that acts out of a sense of duty; and “an action done from duty must wholly exclude the influence of inclination, and with it every object of the will, so that nothing remains which can determine the will except objectively the law and subjectively pure respect of this practical law.”
Our duty towards the moral law arises because it comes to us as an imperative. There are two types of imperatives: hypothetical and categorical.
1. A hypothetical imperative is one which applies only if we enter the sphere of its operation.
2. A technical imperative is an example of a hypothetical imperative. If one wishes to be a doctor there is the technical imperative that one must learn certain skills.
3. A prudential imperative suggests that if we wish to attract someone of the opposite sex it would be prudent to use deodorant. Of course we do not have to—but it is unlikely though that someone will want to come into the sphere of our operation!

The Categorical Imperative

A categorical imperative is one which applies to all people and commands “an action as necessary of itself without reference to another end, that is, as objectively necessary.”
It is categorical because it applies to all rational beings, and it is imperative because it is the principle on which we ought to act.
Kant observed “everything in nature works according to laws. Rational beings alone have the faculty of acting according to the conception of laws.” He concludes from this the following axiom: “Act as if the maxim of your action were to become a universal law of nature.”
The categorical imperative does not give us specific rules rather it gives a rather abstract formula. Once we understand this formula then we can apply it to specific situations.
The individual human being as possessing absolute worth becomes the basis for the supreme principle of morality: “The foundation of this principle is: “rational nature exists as an end in itself. All men everywhere want to be considered persons instead of things for the same reason that I do, and this affirmation of the absolute worth of the individual leads to a second formulation of the categorical imperative which says: So act as to treat humanity, whether in your own person or in that of any other, in every case as an end withal, never as a mean only.”
Immanuel Kant’s final formulation is as follows:
1. “Always so act that the will could regard itself at the same time as making universal law through its own maxim.”
2. Kant speaks of the autonomy of the will, that each person through his own act of will legislates the moral law. This is in contrast with heteronomy in which another is the legislature of law.
3. A heteronomous will is influenced by desires and inclinations. An autonomous will is free and independent and as such is the “supreme principle of morality.”
4. Central to the concept of the autonomy of the will is the idea of freedom, the crucial regulative idea, which Kant employed to distinguish between the worlds of science and morality—the phenomenal and the noumenal worlds:

“I affirm that we must attribute to every rational being which has a will that it has also the idea of freedom and acts entirely under this idea. For in such a being we conceive a reason that is practical, that is, has causality in reference to objects.” ~ Immanuel Kant

The Moral Postulates

Immanuel Kant believed it was impossible to prove that freedom exists. Yet he believed that it had to be assumed that it existed because of our experience of moral obligation, that is, “because I must, I can.” The first moral postulate therefore is that freedom must be assumed.
The second moral postulate is immortality. Although virtue is the supreme good we as rational beings are fully satisfied only when there is a union between virtue and happiness.
1. Though it does not always happen so, we all assume that virtue ought to produce happiness. Kant maintained that the moral law commands us to act not so that we will be happy, but so that our actions will be right.
2. Still, the full realization of a rational being requires that we think of the supreme good as including both virtue and happiness. But our experience shows that there is no necessary connection between virtue and happiness.
3. If we limit human experience to this world, it would then appear impossible to achieve the supreme good in its fullness.
4. Still, the moral law does command us to strive for perfect good, and this implies an indefinite progress towards this ideal: “but this endless progress is possible only on the supposition of the unending duration of the existence and personality of the same rational being, which is called the immortality of the soul.”
The former line of reasoning also compels us toe postulate the existence of God as the grounds for the necessary connection between virtue and happiness.
1. If we mean by happiness “the sate of a rational being in the world with whom in the totality of his experience everything goes according to his wish and will,” then happiness implies a harmony between a person’s will and physical nature.
2. But a person is not the author of the world, nor is he or she capable of ordering nature so as to effect a necessary connection between virtue and happiness.
3. But we do conclude from our conception of the supreme good that virtue and happiness must go together. Consequently, we must postulate “the existence of a cause of the whole of nature which is distinct from nature and which contains the ground of this connection, namely, of the exact harmony of happiness with morality. And thus “it is morally necessary to assume the existence of God.”

“Through the idea of the supreme good as object and final end of the pure practical reason, the moral law leads to religion, that is to the recognition of all duties as divine commands, not as sanctions, that is, as arbitrary commands of an alien will… but as essential laws of every free will in itself, which, however, must be looked on as commands of the supreme Being, because it is only from a morally perfect and at the same time all-powerful will… that we hope to attain the highest good, which the moral law makes it our duty to take as the object of our endeavor.”

References

Dorling Kindersley. (2011). The Philosophy Book. New York: DK Publishing.
Stumpf, Samuel Enoch. (2008). From Socrates to Sartre and Beyond. New York: McGraw Hill Publishing.
Palmer, Donald.(2006). Looking at philosophy:The unbearable heaviness of philosophy made lighter 4th Edition. New York: McGraw Hill Companies.
Gaarder, Jostein. (2004). Sophie’s World. Great Britain: Phoenix House.
http://www.plato.standford.edu
http://www.iep.utm.edu/kantview/

Immanuel Kant