John Dewey wants philosophy to rise above old tired disputes to address new, more vital questions and problems. His views are known as "pragmatism," which emphasizes action and results. Here philosophy isn't a system of beliefs but a practical, empirical method of inquiry.
Sartre's existentialism faces the evil in human existence and sees that humans are responsible for it. He doubts man can make moral progress, yet he embraces the possibilities for human life.