Swiss psychologist Carl Jung is best known for his theories concerning the unconscious — our personalities, dreams, and intuitions. He believed that to develop a “true self,” each person had to distinguish the ego (individual identity) from the collective unconscious (shared symbols and patterns over human history). In that vein, Jung helped establish psychotherapy for people who felt their lives had lost meaning, guiding them to examine their individuality. His studies are a testament to the power of looking inward: When we understand ourselves and our place in the world, it gives us the clarity and insight we need to live with purpose.