Like many proponents of the New Thought philosophy, Marden believed that our thoughts influence our lives and our life circumstances. He said, "We make the world we live in and shape our own environment." ]Yet although he is best known for his books on financial success, he always emphasized that this would come as a result of cultivating one's personal development: "The golden opportunity you are seeking is in yourself. It is not in your environment; it is not in luck or chance, or the help of others; it is in yourself alone."