This image was based on a similar diagram presented by Dr. Richard Knopp of Lincoln Christian University. The Line of Despair originated with Francis Schaeffer.
Begin with Christian Theism and "water-down" each worldview. As Christian Theism gives way to Deism, and Deism gives way to Naturalism you approach the Line of Despair. In other words, once your worldview reaches naturalism the implications of this worldview naturally lead to Nihilism (which most people are unwilling to live with...because living with Nihilism is by definition not possible).
This denial of the ultimate outcome of Nihilism (suicide) leads many to "create" worldviews based more on faith than Christian Theism in order to provide meaning to their existence. As you progress from Marxism to Atheistic Existentialism to Secular Humanism each worldview becomes more socially tenable, however the bottom line is that these worldviews do not provide the best answers to the questions of life, and are based on great leaps of faith.
This was originally posted to my now defunct blog several years ago.
