The 5 Essential People Skills: How to Assert Yourself, Listen to Others, and Resolve Conflicts About the Author Perhaps more than any other person who ever lived, Dale Carnegie changed the human relations movement. His world-famous course has now influenced millions of people. Looking back on his life, Carnegie saw that worry and fear were the forces that held him back. He developed the Dale Carnegie Course as a forum for overcoming worry and fear and for developing human relations and leadership skills.