"It is with Kant that something really and positively new makes its appearance in post-Renaissance moral philosophy. In the process of summing up and concentrating in himself the complex heritage and the long effort of three centuries of thought, he performed a revolutionary task in the realm of ethical philosophy, as in that of speculative philosophy. Not that he wished to destroy or overthrow anything in the realm of morals—on the contrary, his effort was to restore. But in order to construct his imposing edifice he was in fact compelled to transform completely the whole architecture of ethics.”1
Kant, for most of his life a mild-natured philosophy professor at the University of Koenigsberg, Prussia, did not publish his first important work in philosophy until 1781 when he was 57 years old. Yet, from 1781 until his death in 1804, he wrote a series of philosophical works unequalled for their intellectual importance and revolutionary influence since the days of Plato and Aristotle. These include Critique of Pure Reason (1781), Foundation for a Metaphysics of Morals (1785), Critique of Practical Reason (1788), Critique of Judgment (1790), On Religion Within the Bounds of Reason Alone (1792), Perpetual Peace (1795), and Metaphysics of Morals (1803), in addition to lesser works and revised editions of the foregoing. Just as 1776 marked the beginning of a political revolution “heard round the world” by the signing of the American Declaration of Independence, so 1781 marked the beginning of a philosophical upheaval which is still reverberating throughout the world of Western thought.
This second Copernican Revolution, as Kant liked to call his theory, was indeed revolutionary. Before Kant, philosophers had generally agreed that the foundation for the validity of our knowledge was the world of objects. The philosophers held radically divergent views as to what objects really are. Plato, for instance, had claimed that objects were imitations of absolute and immaterial realities which he called Forms; Bishop George Berkeley (1685-1753) had claimed that material objects exist only as ideas in the mind. But most philosophers had followed Aristotle, who held the more or less commonsensical view that objects themselves were the fundamental realities. Knowledge is genuine when ideas accurately reflect the nature of the objects which exist in the spatio-temporal universe. Philosophers seldom questioned our ability to know objects (even though Descartes had raised the issue), but sought to explain what seemed a patent fact, namely, that we do indeed know objects as they really exist.
After 1781, however, things were never the same, for in his Critique of Pure Reason, far from assuming as fact our knowledge of objects in themselves, Kant declared such knowledge to be impossible. The universe, or Nature, is actually a formal system imposed upon our sensations by the mind rather than an objective reality known by its accurate reflection in the mind. Knowledge, said Kant, could extend only to the limits of human experience itself and any attempt to philosophize about matters removed from experience—such as the existence and nature of God, the freedom of the will, and the immortality of the soul—would result in confusion and ultimate contradiction. Kant’s conception overturned all the cherished dogmas of previous philosophy and, in turn, led to the Idealisms of the nineteenth and twentieth centuries, to Phenomenology, and through the latter, to Existentialism.
Nor was Kant’s revolution confined to knowledge of the facts of the universe: it extended as forcefully into the area of moral philosophy. Before Kant, moral philosophers had generally agreed that the ultimate standard for moral judgment could be found in some objective value-object. Aristotle thought that Human Nature was the moral guide to action; the Scholastics of the Middle Ages looked to the Law of God as reflected in man’s rational awareness of the Natural Law; Hume saw the moral standard as an inherent, natural sentiment of approbation. Although these philosophers differed as to what exactly the objective value-object or standard was, they were agreed that it was a guide by which man could decide and choose as he sought goodness, virtue, or moral character.
On the contrary, Kant proclaimed. Since it is impossible to know objects beyond experience, even one’s own human nature or mind as they exist in themselves, but only as they appear to us through our experiences of them, we have no knowledge of any value-object except in so far as it appears to have value. But if we are to avoid a purely subjective moral standard, then we must appeal to reason as the source of moral goodness, not to any preconceived ideal of the perfection of Human Nature or to Divine Command. Morality, then, becomes a matter of inherent consistency of action, not a pursuit of some value-object.
The task of communicating this theory was formidable, for until his time philosophy was expressed in object language, a language in which nouns referred to things and events in themselves and adjectives to characteristics of things and events. Kant found it an impossible task to write in the prevailing terminology of philosophy; he needed a terminology free from the connotations of the previous eras. Anyone who proposes a truly new theory must face such a hurdle. Unfortunately, Kant assumed that readers of the Foundation for a Metaphysics of Morals, his first major work in moral philosophy, would be familiar with his Critique of Pure Reason and so would recognize his usage of certain key expressions. Experience has shown, however, that the Foundation is a far more accessible work than the Critique of Pure Reason and that it is certainly more familiar to nonprofessional students of philosophy. We must examine Kant’s basic terminology before we can profitably begin to examine his moral philosophy itself. Such an introduction need not be lengthy; Kant believed that he was writing a book which would have popular appeal, so he avoided the more formal language encountered in his three Critiques.
Accordingly, the remainder of this introductory chapter will deal with four items:
- Kant’s purpose in writing the Foundation;
- His distinction between speculative and practical reason;
- The meaning of pure reason;
- The meaning of a priori.
The first question which naturally arises about any book is just what it is that the writer is writing about. Some commentators on Kant’s moral philosophy believe that the Foundation is an attempt to discover the ultimate moral law, from which we can deduce our moral obligations; that Kant seeks a standard by which we might judge whether a particular action is right or wrong. Those who so interpret Kant’s work find that Section III of the Foundation, which deals with the problem of freedom of choice, is not relevant to the central theme as they see it and conclude that it is a kind of appendix to the main thesis, dealing with an issue that is indeed important for morality in general but not to any particular moral system.
Another group of commentators believe that the Foundation is a treatise on the metaphysical subject of Freedom, and that Kant uses the field of ethics as the paradigm case for justifying the freedom of the will. Such an interpretation does make Section III an integral part of the whole work, but it overlooks Kant’s emphatic denial that we can prove mans will to be free. It would seem rather odd for Kant to write an entire book to prove or justify something he believed was impossible to prove. Yet, as we shall see, Kant is trying to give a kind of proof for freedom of the will, though it is surely an indirect one. To ignore this would make parts of Section III pointless.
These interpretations are not groundless. Kant is certainly searching for the ultimate standard for moral actions and trying to justify belief in the freedom of the will. Since he firmly insists that freedom is a necessary part of the foundation of morality, he must include a justification for the belief in man’s freedom to make moral choices. Likewise, if a fundamental principle can be established, it will serve as a standard for particular moral laws, even though we may not be able to deduce our particular moral duties from this principle alone.
But neither of these interpretations points to Kant’s primary objective. In the Preface of the Foundation he states quite plainly: “The Foundation, then, has one purpose only: to discover, and justify, the supreme principle of morality.” He seeks the ultimate foundation of morality, that foundation on which the whole structure of moral law must rest if it is to be valid as genuine law of duty.
Any discussion of Kant’s moral theory must begin with a clear understanding of the distinction Kant draws between speculative reason and practical reason. This is an ancient distinction. In his Nicomachean Ethics, Aristotle distinguishes between speculative wisdom and practical wisdom. Both are activities of man’s rational soul, Aristotle explains, but they concern different objects of thought. Speculative wisdom (sophia) is knowledge of eternal, necessary truths, such as mathematics, while practical wisdom (phronesis) is knowledge of the right principles for living the good life.
An analogy may help to illustrate this difference. An automotive engineer may know all there is to know about the mechanical and physical laws involved in the design of a vehicle and yet still not know how to drive. He has theoretical (speculative) knowledge. His wife on the other hand may be an expert driver, yet understand very little of what goes on when she shifts gears. She has practical knowledge, but not theoretical knowledge. A rough distinction would be that theoretical knowledge is knowing that something is so, while practical knowledge is knowing how to perform some action.
In his Critique of Pure Reason, Kant distinguished between the two as follows: “It may be sufficient in this place to define theoretical knowledge or cognition as knowledge of that which is, and practical knowledge as knowledge of that which ought to he.”2 Kant fails to abide by a precise distinction between speculative and practical knowledge, between reason as the source of knowledge of facts in the universe, and reason as the source of knowledge of what we ought to do. At times he states that both are types of knowledge. In the Preface to the Foundation he says, “Ulimately, reason is one; only its functions are different.” Yet in Section II of the same work he asserts that will is nothing else than practical reason. In the Critique of Pure Reason he says that practical reason is “reason in so far as it is itself the cause producing actions.” Generally, however, Kant refers to speculative reason as the rational faculty whereby we know facts, and to practical reason as the rational faculty whereby we know what we ought to do. Knowing what we ought to do is a kind of knowing, surely. But it differs essentially from speculative reason in this: while speculative reason has to do with what was, is, or will be a matter of fact, practical reason has to do with what may not be a matter of fact unless we choose to make it fact by acting. For example, by speculative reason I know that a full moon will rise on a certain evening next month; by practical reason I know that I ought to repay Smith the five dollars that I owe him, or that I ought to drive slowly on icy pavement.
We sometimes hear of a conclusion being deduced or known by “pure reason.” We generally understand this to mean that the process of reasoning was deductive rather than inductive, by syllogism or formal argument rather than by accumulation of factual evidence. Kant’s meaning of “pure reason” is quite different, and the concept is basic to his system.
According to Kant, we have two ways of knowing—that means we have two ways of knowing facts and two ways of knowing what we ought to do. The one way, our everyday way, is knowing through experience, by our senses. Every fact we know about the universe is derived from experience, and every skill we learn is learned through practice. Of course we use our reasoning powers in acquiring such information or such skills, but this use of reason is not what Kant calls pure reason.
Pure reason is reasoning which is “pure of everything derived from experience.” This definition raises an immediate question. If everything we know about the universe, including facts about ourselves, is derived from some kind of experience, what knowledge other than this can be the concern of “pure” reason? The answer to this question constitutes Kant’s unique contribution to the history of thought: pure reason is concerned with the activity of reason itself. What we know of the universe is known through our experiences; but the framework of this knowledge, the systematic construction of knowledge itself, we cannot know through such experiences. To know anything about the universe requires that experiences be meaningful to us, yet the meaningfulness of any experience must be determined by some standard other than the experience itself. This standard, or framework, is a condition3 for all our empirical knowledge, and thus it cannot itself be known by experience, since experience already presupposes this framework. If the framework can be known at all, it must be known quite independently of all experience, that is, by some activity of reason which does not rely on experience of any kind : pure reason.
An example will help. Imagine being seated in a football stadium just before the game. Suddenly half the crowd jumps to its feet, cheering wildly, “Here comes the team!" Heavily padded men pour from the dressing room onto the field and begin limbering up. The spectator counts forty such men, but his minds eye “sees” them as forming a unit, a team. In his mind he unites the individual men into a totality, each man being a part of the whole. We need not linger on this particular example, since it is intended only to show that reason often takes over where perception leaves off; reason does something more, in this case forming into a conceptual unit what the eye sees as separate individuals.
Although this is an activity of reason, it is not yet pure reason, since the material the mind puts together into the conceptual unit, “team", is derived directly from the experiences of the individuals on the playing field. However, let us turn to that mental activity of putting separate sensations into meaningful wholes or conceptual units. If we do this abstractly, without considering any particular occasion of such activity, we are investigating a function of reason independently of experience. This second-order activity of reason, our investigation of reason’s ability to combine individual experiences into conceptual units, does not concern itself with any particular experience at all, but with the activity of the mind itself. This second-order activity of reason Kant calls pure reason.
There are many similarities between the investigation into pure reason and what psychologists refer to as philosophical psychology. Both investigate the workings of reason itself, rather than the objects of reason, as does scientific knowledge. But Kant restricts his investigations of pure reason to the fundamental activities of reason as it forms separate experiences into meaningful conceptual wholes. This too has been a fruitful field of study for the psychologist. But where the psychologist takes this activity of reason as a datum, as a given fact leading to further inquiry, Kant asks whether this unifying activity of reason can justify itself. Does reason unify experiences arbitrarily, or is there some inherent—one might almost say innate—tendency of reason to act within a natural limitation, according to fixed rules which more or less direct such activity? Is knowledge an accumulation of haphazard, but fortuitous, formations of multiple sensations, or is reason itself so structured in its activity that it must unify sensations according to some pre-established system of “laws of knowledge"? By asking such a question, Kant takes nothing in knowledge for granted but subjects reason itself to its most basic criticism—in his own words, to a critique of reason.
Now let us return to the distinction between speculative and practical reason, to see how the concept of pure reason fits into each area. When we investigate the activity of reason as it takes sensations derived from the separate senses and unites them to form experiences of the universe, then we are in the realm of pure speculative reason. This was Kant’s principal task in his first great work, the Critique of Pure Reason. On the other hand, when we investigate the activity of reason as it constructs rules of activity, we are in the realm of pure practical reason. Such is Kant’s task in the Foundation and again in his later Critique of Practical Reason. When Kant speaks of a “Critique of Pure Practical Reason” he means an investigation into the fundamental and purely rational prerequisites for all moral knowledge. In the Foundation he seeks that ultimate principle, framework, condition, or prerequisite which will justify all other moral laws by establishing their objective validity. We can see the importance of this search. If, according to Kant, the mind “molds” raw sense experiences into coherent, meaningful units according to some rational laws of knowledge, it is most important for a theory of knowledge to discover this system of laws, and prove it to be a valid foundation for knowledge of the universe. If a similar activity of mind is necessary for moral knowledge, then it is of tremendous importance for the moral philosopher to discover this system of laws of choice and action and prove it to be a valid foundation for moral principles, for on such a justification the whole validity of morality stands or falls. If there is such a fundamental principle of morality and if we can prove that it is a legitimate basis for moral law, then we have found a single ultimate standard for all moral judgments. If not, morality is a relative matter, little more than a codification of individual preferences or social customs. It requires no great insight to see why this is the most crucial question of moral philosophy.
In traditional logic, the expressions a priori and a posteriori refer respectively to deductive and inductive methods of reasoning. Generally speaking, an a priori argument is one which derives a conclusion from given premisses according to a formal rule (e.g., the syllogism). An a posteriori argument, on the other hand, begins with empirical data about particular objects or events and from this data arrives at a generalization. The latter is the basic inductive method.
Kant uses the terms a priori and a posteriori in different senses. He speaks of a priori and a posteriori concepts, and again, of a priori and a posteriori propositions. Generally, by a priori Kant means “derived from reason"; by a posteriori he means “derived from experience.”
All our concepts of objects, events, and characteristics in the universe are ultimately derived from experience and thus are characterized as a posteriori (e.g., redness, tree, bicycle, Sally, star). An example of an a priori concept is that of change. We experience the succession of one state of an object from a former state, such as the successive notes played on a violin. But we do not actually see the change itself, or in this case, hear it. The combining of the two successive experiences into two parts of the same event, called a change, is a mental process. We perceive with the ear two successive notes, but we experience it mentally as a change. When we think about change itself, we are thinking about an a priori concept.
However, change is not a pure a priori concept, since we do experience change, in a manner of speaking, just as we experienced the team. The concept of change, when considered abstractly, is seen to be due to an operation of reason and not derived from experience alone; but this idea is still tied to the experiences of the successive states, and thus is not free from all experience. After all, we do use the expression, “Watch this water change color,” and surely we do see the water changing color, even though we actually see the successive colors and not some additional characteristic identifiable as the change. Perhaps it would be better to say we see the successive colors as changing, as an event we would classify as a change.
A few concepts, however, are entirely independent of experience, since they serve as the underlying foundations for experience. An example of a pure a priori concept is “substance.” When we slide a plate across a table, we experience the prior and the subsequent locations of the plate and also combine these different experiences into a single event, which we characterize as a change of location of the plate. But the justification for our doing this cannot be based on the experiences themselves, since the experiences are separable, as are the various locations of the plate enroute. We combine the various experiences of the plate’s location into a unity called “change of place” by positing something which serves as a foundation for this unifying activity. Otherwise we might just as well say that the plate in the beginning is an entirely different plate from the plate at the end. We do not do so, however, because we underwrite the change of location with the presupposition that a mere change of location of a plate does not cause it to change into an entirely new plate.
In more philosophical terms, underlying every change there is something which endures through the change, and this substratum is given the abstract name substance. That the concept of substance in our example is completely independent of experience can be understood when we consider that an experience of a plate at one location turning into an entirely different plate at another location would be exactly the same as an experience of a mere change of location of a single plate. We judge that there is only a change of location because we mentally underwrite the event as unified by substance. Substance, then is a pure a priori concept, completely independent of experience. But it is a pure a priori concept of speculative reason, since it applies to objects and events in the universe of fact. A concept which is equally independent of experience, but applies to the world of moral activity, will be a pure a priori concept of practical reason, an example of which is the concept of freedom of the will. Whether or not this is a valid concept is one of the key problems in Kant’s moral theory.
When he turns to propositions, Kant says that an a priori proposition is justified by an appeal to reason, one which is derived from self-evident propositions. The propositions of mathematics are a priori propositions. For example, we know by reason alone, without recourse to experience, that 35 + 36 = 71. An a posteriori proposition, on the other hand, is justified by an appeal to some experience. Any factual statement such as, “The earth is round,” or “Rose Ann has blue eyes,” is an a posteriori proposition. As a general rule of thumb, we can take a priori to mean derived from, or justified by, reason, and a posteriori to mean derived from, or justified by, experience.
Should anyone wonder whether a particular concept or proposition is a priori or a posteriori, whether it is derived from reason or from experience, he may test the concept or proposition by asking whether it can be characterized by necessity. Philosophers have long agreed generally that necessity is an essential characteristic of a priori propositions. For example, it is necessarily true that all bachelors are unmarried and that every effect has a cause. The necessity here is not derived from a poll of bachelors or through a scientific examination of effects but from the meanings of the terms involved. When we understand the meanings of the terms, we see by reason alone that the statements are true, and that to deny them would involve a self-contradiction.
On the other hand, a proposition which is not necessarily true, even though it may be universally true, would not be a priori. We have very good reasons for accepting the universal truth of the proposition, “All men will die,” but we know this to be true only because human experience confirms it. An immortal man, one who never grows older and who remembers events from centuries past, would be a remarkable person indeed, but no self-contradiction is involved in such an idea.
When we approach the matter of moral propositions, we discover that a moral law, such as “Always keep your promises,” seems to involve a kind of necessity. A moral law is not a universal truth based on experience, as though “Always keep your promises,” had the same prudential quality as “When driving, always keep your eye on the road.” The latter rule is good advice, because experience shows that failure to abide by it has unpleasant consequences. The possibility of these unpleasant consequences gives the rule its authority, so to speak. It can be called an a posteriori rule—or, in Kant’s terms, an a posteriori proposition of practical reason.
The situation is not the same with the rule, “Always keep your promises.” To be sure, such a rule could be taken in the same advisory sense as the driving rule. We might give such advice to an aspiring politician, and the validity of our advice would be based upon the probable consequences at the next election. But in such a context we would be giving political advice, not moral instruction. Moral rules differ from advisory rules in a most important respect: unlike advisory rules, moral rules involve necessity. A political candidate may break a political rule (at his risk) without ceasing to be a political candidate, whereas a person cannot break a moral rule without becoming immoral. Or to put it in another way, advisory rules tell us what it would be wise to do while moral rules tell us what we must do. There may be occasions when a driver must remove his eyes from the road or a politician must break a campaign promise. But in some yet to be explained way, a moral rule must always be obeyed. This does not mean that there are never occasions in which a person should break a promise.4 But, when the situation is a moral one, such exceptions arise only in view of some other pre-empting moral rule, such as, “Do not kill another human being.” If I have promised to visit a sick friend, I must keep my promise if I am to be moral; but this necessity must give way to the higher necessity to avoid killing someone. I could not, for instance, speed through a crowded school zone just to get to the hospital before visiting hours were over.
Moral rules, since they are necessary, are a priori rules—in Kant’s terms, a priori propositions of practical reason. This raises a critical question. If moral rules are a priori, then they derive their authority, or moral validity, from reason, not from experience. How does reason arrive at necessary truth in moral propositions? What is the mental procedure whereby practical reason finds necessity? If these practical propositions (rules) are genuinely a priori, how are such a priori propositions of practical reason possible? To answer these questions, one must plunge into the very heart of the whole realm of morality itself. This is just what Kant will do.