Søren Kierkegaard's philosophy has been a major influence in the development of 20th century philosophy, especially Existentialism and Postmodernism. Kierkegaard was a 19th century Danish philosopher who has been called the "Father of Existentialism". His philosophy also influenced the development of existential psychology.
Kierkegaard criticized aspects of the philosophical systems that were brought on by philosophers such as Georg Wilhelm Friedrich Hegel before him and the Danish Hegelians. He was also indirectly influenced by the philosophy of Immanuel Kant. He measured himself against the model of philosophy which he found in Socrates, which aims to draw one's attention not to explanatory systems, but rather to the issue of how one exists.