The influential German philosopher associated with existential thought and humanism is Friedrich Nietzsche. His writings challenged traditional moral values and questioned the existence of absolute truths, advocating for the development of individual perspectives and personal ethics. Nietzsche is best known for concepts such as the will to power and the idea of the Übermensch, or "overman," which emphasize self-overcoming and the creation of one’s own values. His radical questioning of morality and religion has profoundly influenced modern philosophy, literature, and psychology.