Kant indicates right away that the ‘way out’ that characterizes Enlightenment is a process that releases us from the status of ‘immaturity.’ And by ‘immaturity,’ he means a certain state of our will that makes us accept someone else’s authority to lead us in areas where the use of reason is called for. Kant gives three examples: we are in a state of ‘immaturity’ when a book takes the place of our understanding; when a spiritual director takes the place of our conscience; when a doctor decides for us what our diet is to be. Enlightenment is defined by a modification of the pre-existing relation linking will, authority, and the use of reason.
We must also note that this way out is presented by Kant in a rather ambiguous manner. He characterizes it as a phenomenon, an ongoing process; but he also presents it as a task and an obligation. From the very first paragraph, he notes that man himself is responsible for his immature status. Thus it has to be supposed that he will be able to escape from it only by a change that he himself will bring about in himself. Significantly, Kant says that this Enlightenment is a motto, an instruction that one gives oneself and proposes to others. What, then, is this instruction ? Aude sapere: ‘dare to know,’ ‘have the courage, the audacity, to know.’ Thus Enlightenment must be considered both as a process in which people participate collectively and as an act of courage to be accomplished personally. We are at once elements and agents of a single process. They may be actors in the process to the extent that they participate in it; and the process occurs to the extent that people decide to be its voluntary actors.
Kant defines two essential conditions under which mankind can escape from its immaturity. And these two conditions are at once spiritual and institutional, ethical and political.
The first of these conditions is that the realm of obedience and the realm of the use of reason be clearly distinguished. Briefly characterizing the immature status, Kant invokes the familiar expression: ‘Don’t think, just follow orders’; such is, according to him, the form in which military discipline, political power, and religious authority are usually exercised. Humanity will reach maturity when it is no longer required to obey, but when men are told: ‘Obey, and you will be able to reason as much as you like.’ We must note that the German word used here is räsonieren; this word, which is also used in the Critiques does not refer to just any use of reason, but to a use of reason in which reason has no other end but itself: räsonieren is to reason for reasoning’s sake. And Kant gives examples, these too being perfectly trivial in appearance: paying one’s taxes, while being able to argue as much as one likes about the system of taxation, would be characteristic of the mature state; or again, taking responsibility for parish service, if one is a pastor, while reasoning freely about religious dogmas.
We might think that there is nothing very different here from what has been meant, since the sixteenth century, by freedom of conscience: the right to think as one pleases so long as one obeys as one must. Yet it is here that Kant brings into play another distinction, and in a rather surprising way. The distinction he introduces is between the private and public uses of reason. But he adds at once that reason must be free in its public use, and must be submissive in its private use. Which is, term for term, the opposite of what is ordinarily called freedom of conscience.
But we must be somewhat more precise. What constitutes, for Kant, this private use of reason ? In what area is it exercised ? Man, Kant says, makes a private use of reason when he is ‘a cog in a machine’; that is, when he has a role to play in society and jobs to do: to be a soldier, to have taxes to pay, to be in charge of a parish, to be a civil servant, all this makes the human being a particular segment of society; he finds himself thereby placed in a circumscribed position, where he has to apply particular rules and pursue particular ends. Kant does not ask that people practise a blind and foolish obedience, but that they adapt the use they make of their reason to these determined circumstances; and reason must then be subjected to the particular ends in view. Thus there cannot be, here, any free use of reason.
On the other hand, when one is reasoning only in order to use one’s reason, when one is reasoning as a reasonable being (and not as a cog in a machine), when one is reasoning as a member of reasonable humanity, then the use of reason must be free and public. Enlightenment is thus not merely the process by which individuals would see their own personal freedom of thought guaranteed. There is Enlightenment when the universal, the free, and the public uses of reason are superimposed on one another.
source: Michael Foucault comments on Kant’s Essay on Enlightenment