Key thinker: Immanuel Kant (1724–1804)

Immanuel Kant (1724–1804)


Immanuel Kant was born in Königsberg (now Kaliningrad, Russia) to Pietist parents. Pietism was an evangelical movement that emphasized personal faith and individual piety over the doctrine of the Lutheran church. Kant attended the local Pietist school, the Collegium Fridericianum, but rejected his religious education. Instead, he focused on learning the Latin classics, which were also central to the school’s curriculum (

In 1740, he enrolled at the University of Königsberg to study theology, but quickly became more interested in mathematics and physics. At university, Kant was first introduced to the rationalism of Gottfried Leibniz (1646-1716) and the writings of Isaac Newton (1642-1727) and Christian Wolff (1679-1750) ( Kant initially hoped to pursue an academic career, but abandoned this plan following his father’s death in 1746. Kant worked as a private tutor for wealthy families for several years, before returning to the university to teach philosophy in 1754. He would teach in Königsberg until his retirement in 1796 (

Kant was first employed as an unsalaried lecturer at the university. The students who attended his lectures had to pay for them directly, so Kant had to ensure that his courses were popular enough for him to make a living. In 1770, Kant was finally appointed Professor in logic and metaphysics at Königsberg, a position he’d been turned down for fifteen years earlier ( He also began to teach subjects such as pedagogy, natural right, and anthropology (

Kant’s promotion signalled the beginning of his ‘critical’ period. Before 1770, Kant had mainly used the writings of British empiricists, such as Locke (see Chapter 7 on John Locke), Berkeley, and Hume (see Key thinker: David Hume in Chapter 11 on Montesquieu), to supplement German rationalist philosophy without challenging its foundations. But after 1770, Kant began to develop his own position in the three volumes that make up the core of his critical philosophy: Critique of Pure Reason (1781), Critique of Practical Reason (1788), and Critique of Judgment (1790) ( Kant’s critical philosophy soon dominated German philosophy and made him famous across Europe.

Kant spent his final years in Königsberg where he continued to live a highly-regimented life structured around his research and teaching, as well as habits like his daily walk which, it is rumoured, he only missed once to read Jean-Jacques Rousseau’s Émile (see Chapter 9 on Jean-Jacques Rousseau) ( He also dedicated his time to closing a perceived gap in his philosophical system, but never finished this final critical work due to his failing health ( Kant died in Königsberg on February 12, 1804. He was 79 years old.


Kant is considered one of the most important modern European philosophers (see 29.1. Introduction). His philosophical system, transcendental idealism (see Key Concept: Transcendental idealism), inspired the German idealism of G.W.F. Hegel (see Chapter 13 on Marx), Johann Gottlieb Fichte, and Friedrich Schelling. Kant’s ‘theoretical’ philosophy, which includes the Critique of Pure Reason and the Critique of Judgment, deals with the limits to our knowledge of the objective world (see 29.2. Fundamentals of Kant’s Philosophy). His moral and political philosophy, as well as his work in human geography and anthropology (see 29.2. Fundamentals of Kant’s Philosophy), forms the ‘practical’ part of his philosophy.

For Kant, the knowing subject’s mind structures all knowledge before we experience anything at all. The ‘ideal’ aspects that we contribute to our understanding of the world give our knowledge of reality a subjective element. They are composed of purely rational concepts, ideas, or logical demonstrations. Put differently, they do not draw on our experience of the world and are prior to experience. Kant distinguishes between a priori and a posteriori forms of knowledge (see Key concept: a priori—a posteriori). While a posteriori claims must be tested empirically to be judged true or false, the truth of a priori claims can be deduced by reasoning alone. Only a priori knowledge is objective or actual knowledge, since it is universally true.

Kant argues that humans need morality to guide our actions, since we are only imperfect rational beings. He uses the categorical imperative (see Key concept: Categorical Imperative) to demonstrate how we can learn to act in line with abstract, or universal, principles of a priori knowledge. Before we act, he argues, we should ask ourselves whether the action we are about to take should be turned into a universal principle. We cannot rationally believe that theft, for example, should function as a universal moral principle, and therefore we should not act in accordance with it. For Kant, the rightness of moral action can be determined by deductive reasoning.

Kant’s political philosophy (see 29.3. Kant’s Political Philosophy) combines the theoretical and practical elements in his thought. Like Aristotle, Kant argues that we must adopt a teleological standpoint (see Key Concept: Telos in Chapter 2 on Aristotle), which sees things in terms of their ends (i.e., what they are ‘supposed’ to become), if we want to understand human history. Human beings have been given the capacity for the development of full reason, but need to cultivate it to achieve their telos (or final state). The full capacity for reason, however, is not an individual but a species-wide project, which is passed from one generation to the next through the Enlightenment (29.3.1. Universal history and teleology).

Kant suggests that we are progressing towards a perfect civil society. Like Hobbes (see 5.2.2. The Origins of Warre: Hobbes on the State of Nature in Chapter 5 on Thomas Hobbes), he argues that humans’ state of nature is characterized by constant conflict and threats of war. Therefore, human beings must get together to form a state that preserves the law. Kant’s political philosophy builds on Rousseau’s idea of the social contract (see Chapter 9 on Rousseau). But unlike Rousseau, Kant establishes a metaphysical foundation for his ideal civil society. For Kant, the perfect constitution can be deduced from purely a priori concepts. He argues that every state should be a ‘republic’ based on the principles of individual freedom, dependence on a common law, and equality between individuals (see 29.3.2. A priori foundations for political theory).

Kant argues for a positive conception of freedom. He is concerned primarily with human beings’ ability to live a fulfilled life and not merely the absence of domination or coercion. The principle of right he proposes allows for a certain amount of coercion by the state to help citizens transcend the freedom that they have in the state of nature and develop a form of civil freedom that corresponds to the categorical imperative, or the universal laws of freedom (see 29.3.2. A priori foundations for political theory). For Kant, this also applies to the relations between states. In Towards Perpetual Peace (1795), Kant makes the case for a ‘league of nations’ where states, like individuals, give up their natural, or purposeless, freedom for civil freedom. Kant’s cosmopolitan politics prefigure the development of the basic principles of organizations like the United Nations.

Kant bridges the gap between the two dominant traditions of philosophy: continental and analytical philosophy (see 29.1. Introduction). These two strands of philosophy represent two different approaches to philosophising: ideal and non-ideal theory (see 29.4. ‘Ideal’ and ‘Non-Ideal’ Political Theory). John Rawls’ ‘original position’ (see Chapter 32 on John Rawls), for example, uses ideal theory to develop universal principles of justice. The German philosopher Jürgen Habermas, on the other hand (see Key thinker: Jürgen Habermas), draws on Kant’s philosophy to provide normative foundations for Critical Theory. Habermas’ project is an attempt to defend Enlightenment thought against its postmodern critics like Michel Foucault (see Chapter 33 on Michel Foucault) or Jacques Derrida. Although both non-ideal and ideal theories reject the metaphysical elements in Kant’s thought, they owe a substantial debt to his thought.

Critics of ideal theory, like Charles Mills and Carole Pateman (see Chapter 10 on Charles Mills and Carole Pateman), argue that universal Kantian accounts of justice obscure existing injustices by failing to account for histories of oppression, for example. The inadequacies of Kantian universalism are most visible when it comes to the questions of race (see Key concept: race) and colonialism. There is an unresolved tension between the universal idea of a human species developing towards full reason and the racist and Eurocentric elements in Kant’s thought (see 29.4.2. Problems in relation to universal history and teleology: the theology of race). But Mills doesn’t reject Kant’s moral and political philosophy. Instead, he sets out to develop a more inclusive Kantianism that takes seriously feminist and anti-racist critics. Mills shows that we can question the racist or Eurocentric aspects of Kantian thought while acknowledging his contributions to philosophy and countless other subjects.

Further Reading

Flikschuh, Katrin. Kant and Modern Political Philosophy, Cambridge University Press, 2000.

Eze, Emmanuel Chukwudi. ‘The Color of Reason: The Idea of “Race” in Kant’s Anthropology’, in Eze, ed., Postcolonial African Philosophy: A Critical Reader, Oxford: Blackwell, 1997.

Derrida, Jacques. (2002) Who’s Afraid of Philosophy? Right to Philosophy I. Trans Jan Plug. Stanford CA: Stanford University Press.

Benhabib, Seyla. Another Cosmopolitanism, Oxford University Press, Oxford, 2008.

Mills, Charles. ‘Black Radical Kantianism’, Res Philosophica, Vol. 95, No. 1, January 2018: 1–33.

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