One of Kierkegaard’s most influential ideas is his distinction between two kinds of truth. Sometimes he describes these as “objective” and “subjective” truth; sometimes as truth that is known, and truth that is lived. According to Kierkegaard, it is the lived, subjective kind of truth that is most important to each existing human being. Implicit in this claim is a critique of traditional philosophy, for most philosophers – in spite of disagreements about how to define truth, how much of it can be known, and how best to attain it – have thought that truth, if it is possessed at all, is possessed in the form of knowledge.
Kierkegaard is not particularly interested in philosophical debates about whether we really know that the things we perceive exist, or whether we really know that today is Monday. With regard to the truth as knowledge, Kierkegaard tends to emphasise the absence of certainty: for example, he argues that the historical life of Jesus can only be a matter of belief, not knowledge, and he regards the Christian doctrine of the incarnation as a paradox that human reason cannot grasp. But what is most important, in his view, is the way each individual relates themselves to these beliefs, or indeed to any other beliefs, values or ideals. What matters is how beliefs are lived, from day to day and even from moment to moment. Kierkegaard focuses on the question of what it means to be true, or to exist truthfully.
Hovering in the background here is the famous saying attributed to Jesus by the author of John’s gospel: “I am the way, the truth, and the life.” If truth can be a way of living, what does this mean for ordinary human beings? This kind of existential truth, or truthfulness, might be conceived in terms of honesty, integrity, sincerity, or authenticity. For Kierkegaard, however, lived truth is primarily a matter of fidelity – of being true to another person, or to God, or even to oneself. When truth is understood in this way, the fact that we live in time becomes crucial. Kierkegaard often emphasises that human existence is always in a process of becoming, continually changing and developing to such an extent that no two moments are ever the same. But how can a person who is constantly changing be true, or faithful, to anything?
This question of fidelity had a personal significance for Kierkegaard. In 1840, aged 27, he became engaged to 17-year-old Regine Olsen. The couple seem to have been captivated by one another, but almost immediately after proposing to Regine, Kierkegaard changed his mind – although not, apparently, because he did not love her. There followed an agonising few months of private indecision: should he remain true to his promise to marry, or should he be true to his feelings and break it off? And which of these choices meant being true to Regine, and to his own love for her? Eventually he decided to end the engagement, to his young fiancée’s great distress. Kierkegaard later wrote, “If I had had faith, I would have stayed with Regine.”
This time of crisis did not just affect Kierkegaard emotionally, but provided material for his philosophical work. Shortly after breaking up with Regine, he left Copenhagen for Berlin; about four months later, in the spring of 1842, he returned home with the manuscript for his first major work, Either/Or, in his suitcase. This book is written under two different pseudonyms, who offer opposing perspectives on the themes of love, marriage, commitment and decision. And after publishing Either/Or, Kierkegaard wrote Repetition, a short philosophical novella which tells the story of a young man who goes through an existential crisis after breaking off his engagement. Repetition was published on the same day as the better-known Fear and Trembling, which focuses on the biblical story of Abraham’s sacrifice of his son, Isaac – an action that, as Kierkegaard emphasises, seems to lack any moral justification. He seems to have regarded Abraham’s situation as analogous to his own. Towards the end of Fear and Trembling, he writes: “What did Abraham achieve? He remained true to his love.”
One idea that emerged from Kierkegaard’s intense inner struggle over his own love life is that when someone is faced with a choice between different courses of action, no amount of knowledge will be able to resolve the dilemma. Of course, choices can be more or less well-informed. However, decisions about what to do always concern the future – and the future is always unknown. For example, when Kierkegaard decided to marry Regine, he did not know that he would change his mind; when Abraham decided to obey God’s command to sacrifice Isaac, he did not know that the command would be revoked at the last minute. This means that the truth of fidelity is qualitatively different from the kind of truth accessible to knowledge. We often find in Kierkegaard’s work the claim that traditional philosophy and theology – and also, it might added, scientific knowledge – cannot provide existing individuals with guidance about how to live faithfully to others, and also to themselves.