Kant's What Is Enlightenment?: Defining the Modern Project of Reason

Immanuel Kant’s short essay Beantwortung der Frage: Was ist Aufklärung? (“Answering the Question: What Is Enlightenment?”, 1784) is the canonical statement of Enlightenment ideals. The essay defines the Enlightenment as “man’s emergence from self-imposed immaturity,” and it identifies the motto of the Enlightenment as “Sapere aude” — “Dare to know.” The essay is a basic reference for the modern understanding of intellectual freedom and the proper relationship between reason and authority.

The Definition

Kant defines the Enlightenment as “man’s emergence from self-imposed immaturity.” The immaturity, he explains, is “self-imposed” not because it is the result of a lack of understanding, but because it is the result of a lack of courage and resolution to use one’s own understanding without the guidance of another. The motto of the Enlightenment, therefore, is “Sapere aude” — “Dare to know.”

The definition captures the central insight of the Enlightenment: that human beings are capable of thinking for themselves, and that the proper use of human reason requires the courage to question established authority and to pursue the truth on one’s own. The Enlightenment is not, in this sense, a state of arrival; it is a process of liberation from the self-imposed limitations of intellectual dependence.

The Public and Private Uses of Reason

Kant distinguishes between the public and the private uses of reason, and he argues that the two are subject to different requirements. The public use of reason is the use that scholars and writers make of their reason in front of the public — in their books, their lectures, their published essays. The private use of reason is the use that citizens make of their reason in their official capacities — as officers, as judges, as members of the clergy.

Kant argues that the public use of reason must be completely free. The proper use of reason, in the public domain, requires the freedom to publish, to criticize, and to argue without the interference of the authorities. The suppression of the public use of reason is a violation of the very purpose of the Enlightenment.

The private use of reason, however, may legitimately be subject to restrictions. A military officer, for example, must obey the orders of his superiors in the execution of his duties, even if he disagrees with those orders. A clergyman must teach the doctrines of his church, even if he has doubts about those doctrines. The restrictions on the private use of reason are not violations of the Enlightenment, because the private use of reason is concerned with the execution of particular offices, not with the proper use of reason in the public domain.

The distinction between the public and the private uses of reason was a response to the specific circumstances of the Prussian monarchy in which Kant lived. The Prussian monarch, Frederick the Great, was committed to the Enlightenment, but he was also committed to the maintenance of the established order. The distinction between the public and the private uses of reason allowed Kant to defend the freedom of philosophical inquiry while accepting the authority of the state in the execution of particular offices.

The Limits of the Enlightenment

Kant is also careful to address the question of whether we live in an “enlightened age.” His answer is paradoxical: “If it is now asked whether we at present live in an enlightened age, the answer is: No, but we do live in an age of enlightenment.” The point is that the Enlightenment is a process, not a state; the proper task of the present generation is to continue the work of rational inquiry and political reform.

The paradoxical formulation captures an important insight about the nature of the Enlightenment. The Enlightenment is not a state of arrival, in which human beings have finally achieved the perfect use of reason. It is a process of liberation, in which human beings gradually overcome the self-imposed limitations of intellectual dependence. The proper response to the Enlightenment is to participate in this process, to encourage the free use of reason in the public domain, and to work for the political and institutional conditions that will make this freedom possible.

The Legacy

Kant’s essay has had a profound influence on the development of modern thought. The contemporary commitment to the freedom of inquiry, to the importance of the public use of reason, and to the proper relationship between authority and freedom draw on the central arguments of the Kantian essay. The contemporary challenges to the Enlightenment, as defined by Kant, are different from those faced by Kant. The contemporary challenges include the proper response to the spread of misinformation, the proper management of the digital revolution, the proper balance between the free use of reason and the protection of other important values, and the proper response to the various forms of fundamentalism and authoritarianism that have emerged in the contemporary world. The engagement with these challenges is, a continuation of the engagement that Kant began in What Is Enlightenment?.

The basic commitment of Kant — to the principle that the proper use of reason requires the courage to think for oneself, and that the proper role of the state is to create the conditions for the free use of reason — remains a basic commitment of contemporary democratic thought. The defense of intellectual freedom remains, a continuation of the Kantian project.

The Definition

The Public and Private Uses of Reason

The Limits of the Enlightenment

The Legacy

Further Reading