He showed an early interest in philosophy, but his father's experience with the legal system influenced his decision to study law at Heidelberg University.

[1] In 1963 he was awarded the honorary citizenship of the city of Oldenburg in recognition of his outstanding scientific achievements and services to occidental culture.

[10] He remained prominent in the philosophical community and became a naturalized citizen of Switzerland living in Basel until his death on his wife's 90th birthday in 1969.

Jaspers's dissatisfaction with the popular understanding of mental illness led him to question both the diagnostic criteria and the methods of clinical psychiatry.

[citation needed] Jaspers set down his views on mental illness in a book which he published in 1913, General Psychopathology.

He defined primary delusions as autochthonous, meaning that they arise without apparent cause, appearing incomprehensible in terms of a normal mental process.

Jaspers considered primary delusions to be ultimately "un-understandable" since he believed no coherent reasoning process existed behind their formation.

Beginning with modern science and empiricism, Jaspers points out that as people question reality, they confront borders that an empirical (or scientific) method simply cannot transcend.

At this point, the individual faces a choice: sink into despair and resignation, or take a leap of faith toward what Jaspers calls Transcendence.

In making this leap, individuals confront their own limitless freedom, which Jaspers calls Existenz, and can finally experience authentic existence.

[citation needed] Transcendence (paired with the term The Encompassing in later works) is, for Jaspers, that which exists beyond the world of time and space.

[citation needed] Although he rejected explicit religious doctrines,[1] including the notion of a personal God, Jaspers influenced contemporary theology through his philosophy of transcendence and the limits of human experience.

After the war, he resumed his teaching position, and in his work The Question of German Guilt he unabashedly examined the culpability of Germany as a whole in the atrocities of Hitler's Third Reich.

[15] He strongly opposed totalitarian despotism and warned about the increasing tendency towards technocracy, or a regime that regards humans as mere instruments of science or of ideological goals.

With Goethe and Hegel, an epoch had reached its conclusion, and our prevalent way of thinking – that is, the positivistic, natural-scientific one – cannot really be considered as philosophy.

Kant then became the philosopher for me and has remained so ... Nietzsche gained importance for me only late as the magnificent revelation of nihilism and the task of overcoming it.

"[19] Jaspers is also indebted to his contemporaries, such as Heinrich Blücher, from whom he borrowed the term, "the anti-political principle" to describe totalitarianism's destruction of a space of resistance.