Karl Jaspers said this quote

Existenz only becomes clear through reason, reason only has content through Existenz.

~ Karl Jaspers

If philosophy is practice, a demand to know the manner in which its history is to be studied is entailed: a theoretical attitude toward it becomes real only in the living appropriation of its contents from the texts.

~ Karl Jaspers

I began the study of medicine, impelled by a desire for knowledge of facts and of man. The resolution to do disciplined work tied me to both laboratory and clinic for a long time to come.

~ Karl Jaspers

Even scientific knowledge, if there is anything to it, is not a random observation of random objects; for the critical objectivity of significant knowledge is attained as a practice only philosophically in inner action.

~ Karl Jaspers