Existential reasons refer to the motivations or justifications that arise from an individual's existence and experience of life. These reasons often involve deep questions about purpose, meaning, and the nature of being. They can influence personal choices, relationships, and how one perceives the world. In philosophy, existentialism is a movement that explores these themes, with notable figures like Jean-Paul Sartre and Simone de Beauvoir examining how individuals create their own meaning in an indifferent universe. Existential reasons can lead to a greater understanding of oneself and the complexities of human existence.