‘What is Enlightenment?’, full title ‘Answering the Question: What is Enlightenment?’, is a 1784 essay by the philosopher Immanuel Kant (1724-1804). As the longer title suggests, Kant’s essay is a response to a question (posed by a clergyman, Reverend Johann Friedrich Zöllner) concerning the nature of philosophical enlightenment.
What is enlightenment, and how best might it be achieved in a civilised society? These are the key questions Kant addresses, and poses answers to, in his essay, which can be read in full here. Below, we summarise the main points of his argument and offer an analysis of Kant’s position.
‘What is Enlightenment?’: summary
Kant begins ‘What is Enlightenment?’ by asserting that enlightenment is man’s emergence from self-imposed immaturity. He defines ‘immaturity’ here as the inability to use one’s understanding without guidance from another. Kant’s message to his readers is that they should have the courage to use their own understanding, rather than relying on another person’s guidance. That is the ‘motto’ of enlightenment.
Kant acknowledges that remaining ‘immature’ is the easy option for most people, because it’s the lazy option. People can turn to a priest to be their moral conscience for them, or a doctor to determine their diet. Women have been rendered perpetually immature by men in order to keep them meek and ignorant.
The key to enlightenment, Kant asserts, is freedom. If people are granted that, enlightenment will follow. The problem is that most people aren’t free. Even those ‘guardians’ and authority figures who keep others enslaved are themselves victim of this system, which they inherit from those who have gone before them.
Kant distinguishes between what he considers a public freedom to exercise one’s reason (and to question the way things are) and the civic duty we have to obey orders without questioning them. For instance, a soldier engaged in military action cannot afford to question the 
order his superior gives him: he needs to obey the order without question, because that is his ‘civic’ duty at that moment. But off-duty, if that soldier wished to philosophise publicly (e.g., in the role of a scholar) about the flaws in the military system, he should be free to do so.
The same goes for paying taxes. One can argue in parliament, or write pamphlets and newspaper articles about whether high taxation is a good thing (i.e., exercising one’s public duty to question things), but when the taxman sends you a bill, you’d better pay up (i.e., observe your civic duty).
Kant invites us to consider whether a society of priests could set down some rules which would be binding for generations to come. He says this would be wrong, because it denies future generations the chance to question such rules, and social development would be impeded as a result. He also argues that an enlightened monarch would allow his subjects true freedom to think and do as they wish in religious matters, and the monarch should keep his nose out of such matters.
Next, Kant argues that, at the time of writing, people are not living in an ‘enlightened age’ but in an ‘age of enlightenment’: that is, we’ve not attained full enlightenment yet because the process is a long one, but progress is (gradually) being made, thanks largely to the enlightened monarch under whom Kant himself is living, Frederick the Great.
Kant concludes ‘What is Enlightenment?’ by considering the difference between civil and intellectual and spiritual freedom. Perhaps paradoxically, the less civil freedom people have, the more intellectual freedom they gain, and as their intellectual abilities grow, so the health of a particular society grows as governments can start treating people with dignity.
‘What is Enlightenment?’: analysis
‘What is Enlightenment?’ is concerned with every citizen’s public right to use their reason: everyone in a civilised society, Kant argues, should have the freedom to question the status quo and take part in a debate about how society should be governed and maintained. But such public rights and freedoms need to be balanced by the citizen’s private or civic responsibility to obey the law, and observe the status quo, when required to.
In other words, even while we discuss and philosophise about how to improve society, we have to live in the one we currently have, and civilisation would break down if people chose, for instance, to stop following laws they considered unjust or refused to pay their taxes because they disagreed with the levels of taxation.
‘What is Enlightenment?’ is fundamentally a clarion-call to people about the need to ‘dare to be wise’. What is required is not merely intellect but also a willingness to engage one’s reason and exercise that reason upon the everyday things that govern our lives: political systems, financial structures, education, trade, and much else. Enlightenment is mankind’s coming-to-maturity, a willingness to think for oneself and emerge from an immature state where we hand over the power and responsibility to authority figures, whether they’re priests, doctors, teachers, or politicians.