Kierkegaard’s first book, Either/Or (1843), was a dialectical, and poetic discussion in which he sought to justify his break with Regine, and in which set forth a basic tenet of his philosophy: each individual must choose—consciously and responsibly—among the alternatives life presents. Kierkegaard followed this up with other philosophical works: Fear and Trembling (1843), Philosophical Fragments (1844), The Concept of Dread (1844), Concluding Unscientific Postscript to the Philosophical Fragment (1846) and Sickness unto Death.
Kierkegaard’s target was the “system,” as he mockingly put it, of G.W.F. Hegel, the great philosopher of idealism. Kierkegaard attacked Hegel’s attempt to systematize all of reality; Hegel, he said, left out the most important element of human experience: existence itself. ]He went so far as to argue that Hegel’s idealism is a “vehicle capable of destroying the individual.” Kierkegaard felt that no philosophical system could explain the human condition. The experience of reality—the loss of a loved one, the feelings of guilt and dread—was what mattered, not the “idea” of it.
Hegel emphasized universals--Kierkegaard argued for decision and commitment. Hegel sought an objective theory of knowledge upon which everyone could agree; Kierkegaard believed in the subjectivity of truth—meaning that truth is understood and experienced individually.
Existence, Kierkegaard believed, is actual, painful, and more important than “essence” or “idea.” The authentic person wrestles with fundamental questions that cannot be answered rationally.
The only way to live in this painful existence is through faith. But to Kierkegaard, faith is not a mental conviction about doctrine, nor positive religious feelings, but a passionate commitment to God in the face of uncertainty. Faith is a risk--the “leap of faith”--an adventure that requires the denial of oneself. To choose faith is what brings authentic human existence. This is the “existentialism” that Kierkegaard is considered the founder of—though later existentialists had significantly different agendas than his.
In his later writings—Works of Love (1847), Christian Discourses (1848), and Training in Christianity (1850)— Kierkegaard tried to clarify the true nature of Christianity. The greatest enemy of Christianity, he argued, was “Christendom”—the cultured and respectable Christianity of his day. The tragedy of easy Christianity is that existence has ceased to be an adventure and a constant risk in the presence of God but has become a form of morality and a doctrinal system. Its purpose is to simplify the matter of becoming a Christian. This is just paganism, “cheap” Christianity, with neither cost nor pain, Kierkegaard argued. It is like war games, in which armies move and there is a great deal of noise, but there is no real risk or pain—and no real victory. Kierkegaard believed the church of his day was merely playing at Christianity.
Kierkegaard became increasingly convinced that his calling was in making Christianity difficult. He was to remind people of his day that to be truly Christian, one must become aware of the cost of faith and pay the price. He believed that only by making things difficult—by helping people become aware of the pain, guilt, and feelings of dread that accompany even the life of faith—could he help Christians hear God again.
A few good books on Søren Kierkegaard (from beginner to advanced)
Søren Kierkegaard: A Biography / Joakim Graff
Kierkegaard: An Essential Introduction / Michael Watts
Kierkegaard: An Introduction / C.Stephan Evans
Kierkegaard: A Single Life / Stephan Backhouse