Kierkegaard: Philosophy of Existence Summary

Who was Søren Kierkegaard

Søren Kierkegaard was born on 5 May 1813 in Copenhagen, into a well-off family. His father, Michael Kierkegaard, was a successful merchant but also a man prone to melancholy, and he passed on to his son a deep sense of guilt that stayed with him for life. In 1840 Kierkegaard got engaged to Regine Olsen, then eighteen; the following year he broke off the engagement, convinced his own temperament made him unfit for marriage, rather than reveal to her a personal secret he considered incompatible with married life. Shortly before his death he used the newspaper Fædrelandet to launch a public, pointed attack on the Danish state church — a challenge to established religious authority that, under very different circumstances, echoes the one Martin Luther raised centuries earlier with the Protestant Reformation. He died in Copenhagen on 11 November 1855, a few weeks after being hospitalized, at age 42.

His output falls into two strands. One is signed under different pseudonyms: Victor Eremita, Johannes de Silentio, Johannes Climacus, Vigilius Haufniensis, Anti-Climacus. The other is signed with his own name, such as Works of Love, published in 1847. The pseudonyms are not a literary quirk: each voice argues its own point of view, often in tension with the others, and Kierkegaard uses irony and satire to carry an argument forward without speaking in the first person.

Kierkegaard’s target: Hegel’s system

In a common reading, the refusal to build a philosophical system makes Kierkegaard a radical opponent of Hegel. The pseudonym Johannes Climacus pushes the objection to its limit: only God could build a complete system of existence, not a human being who exists in time and cannot view their own life from a point outside it. It is a modern version of an older question, the one about what makes an individual real in front of a universal category that Aristotle and Plato had already approached in opposite ways.

To see what Kierkegaard rejects, it helps to see where he starts. Hegel proposes a method, dialectic, that in theory can reveal the whole of reality as a single rational process. Kierkegaard mainly targets the starting ambition behind a project like that: the same drive to close existence inside a finished system also underlies Spinoza’s single substance, built from a geometric order meant to explain everything. For Kierkegaard that order stays outside the person who exists and chooses, and no system can choose in their place.

A practical example: someone who explains away a personal failure by reading it as a necessary stage in a larger design is treating their own life the way a Hegelian system would, from the outside. For Kierkegaard that same failure is lived through concrete choices: in real life, nobody actually views their own existence from an outside vantage point.

The three spheres of existence

A common reading of Kierkegaard’s thought distinguishes three spheres, or stages, of existence. The aesthetic sphere is built around immediate pleasure and asks nothing lasting of the person. The ethical sphere brings in duty and commitment: a person ties themselves to a job, a relationship, a promise, and answers for it over time. The religious sphere, for Kierkegaard, calls for the inwardness of a believer: genuine faith is a personal, passionate claim, one that demands more than simply knowing facts.

There is no sharp line between one sphere and the next. Between the aesthetic and the ethical lies a zone crossed by irony. Between the ethical and the religious, a zone crossed by humor. The pseudonym Johannes Climacus sums up the move toward the religious sphere with two provocative formulas, “truth is subjectivity” and “subjectivity is untruth”: religious truth is claimed first-hand, with a passion no outside check could supply. For Kierkegaard, faith begins at the exact point where reason stops.

Anxiety in Kierkegaard

In The Concept of Anxiety, signed under the pseudonym Vigilius Haufniensis, Kierkegaard describes anxiety, in German Angst, as the dizziness of freedom. It appears when the spirit has to hold body and soul together at the moment of choosing.

The same work also calls it an ambivalent feeling, both attraction and repulsion, that anticipates the pleasure of freedom together with the weight of the responsibility freedom brings. It is the natural response to a life lived with intellectual independence, taking on responsibility for one’s own choices.

The major works, in brief

Between 1843 and 1849 Kierkegaard published, in quick succession, the works that remain the core of his thought. Either/Or, edited by the fictional Victor Eremita, sets the aesthetic and ethical ways of life side by side. Fear and Trembling, signed Johannes de Silentio, draws on the biblical story of Abraham to question the relationship between faith and ethics. The Concept of Anxiety, signed Vigilius Haufniensis, develops the theme of the previous section. The Sickness unto Death, signed Anti-Climacus, treats despair as a condition of the spirit.

To these can be added Philosophical Fragments and the Concluding Unscientific Postscript, both signed Johannes Climacus, and Repetition, signed Constantin Constantius, published already in 1843. Each of these works deserves a reading of its own; here they remain an introduction, a starting point.

The legacy of an uncomfortable thinker

Kierkegaard’s thought influences the phenomenological and existentialist tradition of the 20th century, from Heidegger to Sartre, from Jaspers to Marcel and Levinas. He becomes a major intellectual figure mostly after the First World War, when he is rediscovered across Europe. The label “first existentialist” has followed him ever since, but the Stanford Encyclopedia of Philosophy flags a caution: applied to a thinker for whom faith remains the destination, it risks misleading readers who tie existentialism mainly to atheist thinkers like Sartre.