The following Glossary lists Kant’s most important technical terms, together with a simple definition of each. (The terms ‘judicial’, ‘perspective’ and ‘standpoint’ are the only ones Kant himself does not use as technical terms.) It was originally written as a study aide to help make the intricate web of Kant’s terminology comprehensible to students who had little or no familiarity with Kant’s writings. Where relevant, the opposite term is given in curved brackets at the end of the definition. When a word defined herein (or a slightly different form of such a word) is used in the course of defining some other word in this Glossary, its first occurrence in that definition will be in italics.
a posteriori: a way of gaining knowledge by appealing to some particular experience(s). This method is used to establish empirical and hypothetical truths. (Cf. a priori.)
a priori: a way of gaining knowledge without appealing to any particular experience(s). This method is used to establish transcendental and logical truths. (Cf. a posteriori.)
aesthetic: having to do with sense-perception. In the first Critique this word refers to space and time as the necessary conditions for sense-perception. The first half of the third Critique examines the subjective purposiveness in our perception of beautiful or sublime objects in order to construct a system of aesthetic judgment. (Cf. teleological.)
analysis: division of a representation into two opposing representations, with a view towards clarifying the original representation. Philosophy as metaphysics employs analysis more than synthesis. (Cf. synthesis.)
analytic: a statement or an item of knowledge which is true solely because of its conformity to some logical laws. (Cf. synthetic.)
appearance: an object of experience, when viewed from the transcendental perspective. Though often used as a synonym for phenomenon, it technically refers to an object considered to be conditioned by space and time, but not by the categories. (Cf. thing in itself.)
architectonic: the logical structure given by reason (especially through the use of twofold and threefold divisions), which the philosopher should use as a plan to organize the contents of any system.
autonomy: an action which is determined by the subject’s own free choice (see will). In the second Critique, moral action is defined as being autonomous. (Cf. heteronomy.)
categorical imperative: a command which expresses a general, unavoidable requirement of the moral law. Its three forms express the requirements of universalizability, respect and autonomy. Together they establish that an action is properly called ‘morally good’ only if (1) we can will all persons to do it, (2) it enables us to treat other persons as ends and not merely as the means to our own selfish ends, and (3) it allows us to see other persons as mutual law-makers in an ideal ‘realm of ends’.
categories: the most general concepts, in terms of which every object must be viewed in order for it to become an object of empirical knowledge. The four main categories (quantity, quality, relation and modality) each have three sub-categories, forming a typical example of a twelvefold, architectonic pattern. (Cf. space and time.)
concept: the active species of representation, by means of which our understanding enables us to think. By requiring perceptions to conform to the categories, concepts serve as ‘rules’ allowing us to perceive general relations between representations. (Cf. intuition.)
conscience: the faculty of the human subject which enforces the moral law in a particular way for each individual by providing an awareness of what is right and wrong in each situation.
constitutive: playing a fundamental role in making up some type of knowledge. (Cf. regulative.)
Copernican revolution: in astronomy, the theory that the earth revolves around the sun; in philosophy, the (analogous) theory that the subject of knowledge does not remain at rest, but revolves around (i.e., actively determines certain aspects of) the object. Thus, the formal characteristics of the empirical world (i.e., space and time and the categories) are there only because the subject’s mind puts them there, transcendentally.
Critical: Kant’s lifelong approach to philosophy which distinguishes between different perspectives and then uses such distinctions to settle otherwise unresolvable disputes. The Critical approach is not primarily negative, but is an attempt to adjudicate quarrels by showing the ways in which both sides have a measure of validity, once their perspective is properly understood. Kant’s system of Critical philosophy emphasizes the importance of examining the structure and limitations of reason itself.
Critique: to use the method of synthesis together with a critical approach to doing philosophy. This term appears in the titles of the three main books in Kant’s Critical philosophy, which adopt the theoretical, practical and judicial standpoints, respectively. The purpose of Critical philosophy is to prepare a secure foundation for metaphysics. (Cf. metaphysics.)
disposition: the tendency a person has at a given point in time to act in one way or another (i.e., to obey the moral law or to disobey it). (Cf. predisposition.)
duty: an action which we are obligated to perform out of respect for the moral law.
empirical: one of Kant’s four main perspectives, aiming to establish a kind of knowledge which is both synthetic and a posteriori. Most of the knowledge we gain through ordinary experience, or through science, is empirical. ‘This table is brown’ is a typical empirical statement. (Cf. transcendental).
experience: the combination of an intuition with a concept in the form of a judgment. ‘Experience’ in this ‘mediate’ sense is a synonym for ’empirical knowledge’. The phrase ‘possible experience’ refers to a representation which is presented to our sensibility through intuition, but is not yet known, because it has not been presented to our understanding through concepts. ‘Experience’ in this sense is ‘immediate’ and contrasts with ‘knowledge’.
faculty: a fundamental power of human subjects to do something or perform some rational function.
faith: a rational attitude towards a potential object of knowledge which arises when we are subjectively certain it is true even though we are unable to gain theoretical or objective certainty. By contrast, knowledge implies objective and subjective certainty, while opinion is the state of having neither objective nor subjective certainty. Kant encouraged a more humble approach to philosophy by claiming to deny knowledge in order to make room for faith-i.e., by distinguishing between what we can know empirically and what is transcendent, which we can approach only by means of faith.
formal: the active or subjective aspect of something-that is, the aspect which is based on the rational activity of the subject. (Cf. material.)
heteronomy: an action which is determined by some outside influence (i.e., some force other than the freedom given by practical reason, such as inclination) impelling the subject to act in a certain way. Such action is nonmoral (i.e., neither moral nor immoral). (Cf. autonomy.)
hypothetical: one of Kant’s four main perspectives, aiming to establish a kind of knowledge which is both analytic and a posteriori (though Kant himself wrongly identified it as synthetic and a priori). Most metaphysical knowledge is properly viewed from this perspective, instead of from the speculative perspective of traditional metaphysics. ‘There is a God’ is a typical hypothetical statement. (Cf. logical).
ideas: the species of representation which gives rise to metaphysical beliefs. Ideas are special concepts which arise out of our knowledge of the empirical world, yet seem to point beyond nature to some transcendent realm. The three most important metaphysical ideas are God, freedom and immortality.
imagination: the faculty responsible for forming concepts out of the ‘manifold of intuition’ and for synthesizing intuitions with concepts to form objects which are ready to be judged.
inclination: the faculty or object which motivates a person to act in a heteronomous way. Following inclinations is neither morally good nor morally bad, except when doing so directly prevents a person from acting according to duty-i.e., only when choosing to obey an inclination results in disobedience to the moral law.
intelligible: presented to the subject without any material being provided by sensibility. It is more or less equivalent to the terms supersensible and transcendent. (Cf. sensible.)
intuition: the passive species of representation, by means of which our sensibility enables to have sensations. By requiring appearances to be given in space and time, intuitions allow us to perceive particular relations between representations, thereby limiting empirical knowledge to the sensible realm. (Cf. concept.)
judgment: in the first Critique, the use of the understanding by which an object is determined to be empirically real, through a synthesis of intuitions and concepts. The third Critique examines the form of our feelings of pleasure and displeasure in order to construct a system based on the faculty of judgment (= the judicial standpoint) in its aesthetic and teleological manifestations. (Cf. reason.)
judicial: one of Kant’s three main standpoints, relating primarily to experience-i.e., to what we feel, as opposed to what we know or desire to do. Judicial reason is virtually synonymous with ‘Critique’ itself, and is concerned with questions about the most profound ways in which we experience the world. Finding the source of two examples of such experiences is the task of the third Critique. (Cf. theoretical and practical.)
knowledge: the final goal of the understanding in combining intuitions and concepts. If they are pure, the knowledge will be transcendental; if they are impure, the knowledge will be empirical. In a looser sense, ‘knowledge’ also refers to that which arises out adopting any legitimate perspective.
logical: one of Kant’s four main perspectives, aiming to establish a kind of knowledge which is both analytic and a priori. Hence it is concerned with nothing but the relationships between concepts. The law of noncontradiction (A is not -A) is the fundamental law of traditional, Aristotelian logic. (If we call this ‘analytic’ logic, then ‘synthetic’ logic would be based on the opposite law of ‘contradiction’ [A is -A].) ‘All bachelors are unmarried’ is a typical logical statement. (Cf. hypothetical.)
material: the passive or objective aspect of something-that is, the aspect which is based on the experience a subject has, or on the objects given in such an experience. (Cf. formal.)
maxim: the material rule or principle used to guide a person in a particular situation about what to do (e.g., ‘I should never tell a lie’). It thus provides a kind of bridge between a persons inner disposition and outer actions.
metaphysics: the highest form of philosophy, which attempts to gain knowledge of the ideas. Because the traditional, speculative perspective fails to succeed in this task, Kant suggests a new, hypothetical perspective for metaphysics. Metaphysics can succeed only when it is preceded by Critique. (Cf. Critique.)
moral law: the one ‘fact’ of practical reason, which is in every rational person, though some people are more aware of it than others. The moral law, in essence, is our knowledge of the difference between good and evil, and our inner conviction that we ought to do what is good. (See categorical imperative.)
noumenon: the name given to a thing when it is viewed as a transcendent object. The term ‘negative noumenon’ refers only to the recognition of something which is not an object of sensible intuition, while ‘positive noumenon’ refers to the (quite mistaken) attempt to know such a thing as an empirical object. These two terms are sometimes used loosely as synonyms for ‘transcendental object’ and ‘thing in itself’, respectively. (Cf. phenomenon.)
object: a general term for any ‘thing’ which is conditioned by the subject’s representation, and so is capable of being known. The thing in itself is a thing which cannot become an object. (Cf. subject; see thing in itself.)
objective: related more to the object or representation out of which knowledge is constructed than to the subject possessing the knowledge. Considered transcendentally, objective knowledge is less certain than subjective knowledge; considered empirically, objective knowledge is more certain. (Cf. subjective.)
perspective: a way of thinking about or considering something; or a set of assumptions from which an object can be viewed. Knowing which perspective is assumed is important because the same question can have different answers if different perspectives are assumed. Kant himself does not use this word, but he uses a number of other expressions (such as standpoint, way of thinking, employment of understanding, etc.) in precisely this way. The main Critical perspectives are the transcendental, empirical, logical and hypothetical.
phenomenon: the object of knowledge, viewed empirically, in its fully knowable state (i.e., conditioned by space and time and the categories). (Cf. noumenon.)
practical: one of Kant’s three main standpoints, relating primarily to action -i.e., to what we desire to do as opposed to what we know or feel. Practical reason is a synonym for will; and these two terms are concerned with questions of morality. Finding the sources of such action is the task of the second Critique. (Cf. theoretical and judicial.)
predisposition: the natural tendency a person has, apart from (or before having) any experience, to be morally good or evil. (Cf. disposition.)
pure: not mixed with anything sensible. Although its proper opposite is ‘impure’, Kant normally opposes ‘pure’ to ’empirical’.
rational: grounded in the faculty of reason rather than in sensibility. (See also intelligible.)
reality: if regarded from the empirical perspective, this refers to the ordinary world of nature; if regarded from the transcendental perspective, it refers to the transcendent realm of the noumenon.
reason: in the first Critique, the highest faculty of the human subject, to which all other faculties are subordinated. It abstracts completely from the conditions of sensibility. The second Critique examines the form of our desires in order to construct a system based on the faculty of reason (= the practical standpoint). Reason’s primary function is practical; its theoretical function, though often believed to be more important, should be viewed as having a secondary importance. (Cf. judgment.)
regulative: providing important guidelines for how knowledge should be used, yet not itself playing any fundamental role in making up that knowledge. (Cf. constitutive.)
religion: the way of acting, or perspective, according to which we interpret all our duties as divine commands.
representation: the most general word for an object at any stage in its determination by the subject, or for the subjective act of forming the object at that level. The main types of representations are intuitions, concepts and ideas. In the first Critique, the understanding is the dominant faculty in processing representations, while in the third Critique the faculty of imagination is dominant. Sometimes translated as ‘presentation’.
schematism: the function of the faculty of imagination, through which concepts and intuitions are combined, or synthesized, according to a rule (called a schema). In the first Critique, this function is presented as one of the steps required in order for the understanding to produce empirical knowledge.
sensibility: the faculty concerned with passively receiving objects. This is accomplished primarily in the form of physical and mental sensations (via ‘outer sense’ and ‘inner sense’, respectively). However, such sensations are possible only if the objects are intuited, and intuition depends on space and time existing in their pure form as well. (Cf. understanding.)
sensible: presented to the subject by means of sensibility. (Cf. intelligible.)
space and time: considered from the empirical perspective, they form the context in which objects interact outside of us; considered from the transcendental perspective, they are pure, so they exist inside of us as conditions of knowledge. (Cf. categories.)
speculative: the illusory perspective which wrongly uses reason in a hopeless attempt to gain knowledge about something transcendent. Sometimes used loosely as a synonym of theoretical.
standpoint: the special type of perspective which determines the point from which a whole system of perspectives is viewed. The main Critical standpoints are the theoretical, practical and judicial.
subject: a general term for any rational person who is capable of having knowledge. (Cf. object; see also representation.)
subjective: related more to the subject than to the object or representation out of which knowledge is constructed. Considered transcendentally, subjective knowledge is more certain that objective knowledge; considered empirically, subjective knowledge is less certain. (Cf. objective.)
summum bonum: Latin for highest good. This is the ultimate goal of the moral system presented in the second Critique; it involves the ideal distribution of happiness in exact proportion to each person’s virtue. In order to conceive of its possibility, we must postulate the existence of God and human immortality, thus giving these ideas practical reality.
supersensible: see intelligible and transcendent.
synthesis: integration of two opposing representations into one new representation, with a view towards constructing a new level of the object’s reality. Philosophy as Critique employs synthesis more than analysis. On the operation of synthesis in the first Critique, see imagination. (Cf. analysis.)
synthetic: a statement or item of knowledge which is known to be true because of its connection with some intuition. (Cf. analytic.)
system: a set of basic facts or arguments (called ‘elements’) arranged according to the order of their logical relationships, as determined by the architectonic patterns of reason. Kant’s Critical philosophy is a System made up of three subordinate systems, each defined by a distinct standpoint, and each made up of the same four perspectives.
teleological: having to do with purposes or ends. The second half of the third Critique examines the objective purposiveness in our perception of natural organisms in order to construct a system of teleological judgment.
theoretical: one of Kant’s three main standpoints, relating primarily to cognition-i.e., to what we know as opposed to what we feel or desire to do. Theoretical reason is concerned with questions about our knowledge of the ordinary world (the world science seeks to understand). Finding the source of such knowledge is the task of the first Critique, which would best be entitled the Critique of Pure ‘Theoretical’ Reason. (Cf. practical and judicial; see speculative.)
thing in itself: an object considered transcendentally apart from all the conditions under which a subject can gain knowledge of it. Hence the thing in itself is, by definition, unknowable. Sometimes used loosely as a synonym of noumenon. (Cf. appearance.)
time: see space and time.
transcendent: the realm of thought which lies beyond the boundary of possible knowledge, because it consists of objects which cannot be presented to us in intuition-i.e., objects which we can never experience with our senses (sometimes called noumena). The closest we can get to gaining knowledge of the transcendent realm is to think about it by means of ideas. (The opposite of ‘transcendent’ is ‘immanent’.)
transcendental: one of Kant’s four main perspectives, aiming to establish a kind of knowledge which is both synthetic and a priori. It is a special type of philosophical knowledge, concerned with the necessary conditions for the possibility of experience. However, Kant believes all knowing subjects assume certain transcendental truths, whether or not they are aware of it. Transcendental knowledge defines the boundary between empirical knowledge and speculation about the transcendent realm. ‘Every event has a cause’ is a typical transcendental statement. (Cf. empirical.)
transcendental object: an object considered transcendentally insofar as it has been presented to a subject, but is not yet represented in any determined way-i.e., not yet influenced by space and time or by the categories. Also called an ‘object in general’.
understanding: in the first Critique, the faculty concerned with actively producing knowledge by means of concepts. This is quite similar to what is normally called the mind. It gives rise to the logical perspective, which enables us to compare concepts with each other, and to the empirical perspective (where it is also called judgment), which enables us to combine concepts with intuitions in order to produce empirical knowledge. The first Critique examines the form of our cognitions in order to construct a system based on the faculty of understanding (= the theoretical standpoint). (Cf. sensibility.)
will: the manifestation of reason in its practical form (see practical). The two German words, ‘Willkür’ and ‘Wille’ can both be translated in English as ‘will’. Willkür refers to the faculty of choice, which for Kant is just one (empirical) function of the more fundamental faculty of practical reason (= Wille).