Jaspers was born in Oldenburg in 1883 to a mother from a local farming community, and a jurist father. He showed an early interest in philosophy, but his father's experience with the legal system undoubtedly influenced his decision to study law at university. It soon became clear that Jaspers did not particularly enjoy law, and he switched to studying medicine in 1902.
Jaspers graduated from medical school in 1909 and began work at a psychiatric hospital in Heidelberg where Emil Kraepelin had worked some years earlier. Jaspers became dissatisfied with the way the medical community of the time approached the study of mental illness and set himself the task of improving the psychiatric approach. In 1913 Jaspers gained a temporary post as a psychology teacher at Heidelberg University. The post later became permanent, and Jaspers never returned to clinical practice.
At the age of 40 Jaspers turned from psychology to philosophy, expanding on themes he had developed in his psychiatric works. He became a renowned philosopher, well respected in Germany and Europe. In 1948 Jaspers moved to the University of Basel in Switzerland. He remained prominent in the philosophical community until his death in Basel in 1969.
Jaspers' dissatisfaction with the popular understanding of mental illness led him to question both the diagnostic criteria and the methods of clinical psychiatry. He published a revolutionary paper in 1910 in which he addressed the problem of whether paranoia was an aspect of personality or the result of biological changes. Whilst not broaching new ideas, this article introduced a new method of study. Jaspers studied several patients in detail, giving biographical information on the people concerned as well as providing notes on how the patients themselves felt about their symptoms. This has become known as the biographical method and now forms the mainstay of modern psychiatric practice. Jaspers set about writing his views on mental illness in a book which he published in 1913 as General Psychopathology. The two volumes which make up this work have become a classic in the psychiatric literature and many modern diagnostic criteria stem from ideas contained within them. Of particular importance, Jaspers believed that psychiatrists should diagnose symptoms (particularly of psychosis) by their form rather than by their content. For example, in diagnosing a hallucination, the fact that a person experiences visual phenomena when no sensory stimuli account for it (form) assumes more importance than what the patient sees (content).
Jaspers felt that psychiatrists could also diagnose delusions in the same way. He argued that clinicians should not consider a belief delusional based on the content of the belief, but only based on the way in which a patient holds such a belief (see delusion for further discussion). Jaspers also distinguished between primary and secondary delusions. He defined primary delusions as autochthonous meaning arising without apparent cause, appearing incomprehensible in terms of normal mental processes. (This is a distinctly different use of the term autochthonous than its usual medical or sociological meaning of indigenous.) Secondary delusions, on the other hand, he classified as influenced by the person's background, current situation or mental state.
Jaspers considered primary delusions as ultimately 'un-understandable,' as he believed no coherent reasoning process existed behind their formation. This view has caused some controversy, and the likes of R. D. Laing and Richard Bentall have criticised it, stressing that taking this stance can lead therapists into the complacency of assuming that because they do not understand a patient, the patient is deluded and further investigation on the part of the therapist will have no effect.
Most commentators associate Jaspers with the philosophy of existentialism, in part because he draws largely upon the existentialist roots of Nietzsche and Kierk
"L’ottimismo asserisce […] che la verità apporta sempre e solo del bene. Ma la verità può avere, per la nostra visuale limitata e finita, conseguenze così tremende che Schiller ha scritto: solo l’errore è la vita e la verità è la morte." (p. 69)
Karl Jaspers has some harsh words for Marxism and the psychoanalysis fashions of the time in which he wrote Reason and Anti-Reason in Our Time, these words presented in the first of three parts of the book. Those three parts, The Challenge of the Scientific Method, Reason, and Reason in its Struggle, are based on three lectures he gave in series. He waxes a bit purple and poetic in parts of the second of these lectures, but cogent analysis of the challenges pop culture sets in the path of rationality, the nature of the human act of reasoning, and the value it brings us as the only honest (and, consequently, perhaps asymptotic) approach to truth, all pervade the text. Along with the brilliance of his characterization of the matters relevant to his theses, it makes for a fascinating read.
Jaspers sets the always-outnumbered champions of reason in their proper place, outnumbered but not outgunned as he reveals the remarkable tendency of reason to arise anew after every effort to put it down, a phenomenon he describes as not emerging from the nature of the human condition but rather consciously pursued (and often at great cost) by leverage of the condition of freedom and exercise of the faculty of choice. A nearly pocket-sized, largely featureless red hardcover, my copy of Reason and Anti-Reason in Our Time came into my possession by some now-forgotten happenstance with (intellectually rather unimpressive) notes handwritten in the margins of the book's yellowing pages by someone using dismayingly poor penmanship, lending it a well-loved charm and warm sense of inspirational authority that other copies will probably lack. The content itself, however, is a stellar work of philosophical rationalism that must benefit anyone with the wit and will to understand it, regardless of the form and condition of the published book, and my only possible regret is that I had not plucked it from my to-read shelf sooner. It is getting a place of honor on another shelf tonight, among books that have special significance for me. As I have with the Tao Te Ching, I rather suspect I will return to it from time to time in my life.
The term "philosophy" in literal translation yields the meaning "love of wisdom". This is a book for authentic philosophers, who exercise Reason in search of the wisdom they love.