Reason alone does not overcome nihilism. Indeed, not even if reason establishes divine command morality, is nihilism decisively overcome. See results of my: Overview of Posts Confronting Nihilism . There are two dimensions in overcoming nihilism: attitudinal and intellectual. A firm sense of purpose for living provides an attitudinal antidote to nihilism. A firm sense of purpose is faith. The stability of faith is based on a purpose which is a fixed point. Reason fixes the point by closing the question of for what purpose the purpose is pursued. For instance, a person can live a purpose driven life by striving in thought, word and deed to be on the right side of the history of human development. Such a person, consciously or unconsciously, resolves not to undercut the existential significance of the purpose by dwelling on questions about what exactly it is to be on the right side of history and why it matters. Another might live to do what is right because it is right. This stoic believer in morality brushes aside any question about the purpose of living for duties sake. A third might live to do what God commands because God commands it. In this case, questioning the purpose of obeying God is dismissed as blasphemous.
The proposed purposes are universal: for all human beings. We, individually, have these purposes because that purpose is the purpose of being human. Suppose the purpose for life is said to be only for me or only for a particular society. The questions: Why me? Why us? are obviously open questions.
Although it is odd to ask for what purpose the purposes are pursued sense can be made of asking for what purpose they are pursued. The reality which give rise to the problem of evil is available to undercut even the most firm faith. See The Problem of Evil as the Cornerstone of a Christian World View and The Problem of Evil as a Cornerstone of a Nihilistic World View. Sense can be made of asking for what purpose we pursue them because reason shows that they are unattainable. Reason shows us that we are subject to sin and death. We cannot live up to these ideals. We simply have not been and are not now in pursuit of these ideals. Individually and collectively we are hopeless failures. In any event, death eventually takes away every individual and civilization. Because of intellectual knowledge of death and sin, the attitudinal antidotes to nihilism are vulnerable.
I have come to the end of what philosophy, including natural theology and natural moral theology, can accomplish in regard to providing an antidote to nihilism. Philosophy, via the reality underlying the problem of evil undercuts any purpose for life proposed by philosophy as ideology.
What is to be done? One can accept nihilism. But intellectual honesty does not require accepting nihilism even if nihilism cannot be set aside by human intelligence alone. See Does Respect for Truth Require Nihilism? William James argued well for this point in his well known The will to believe. The other alternative is to “tough it out” by holding fast to faith in some proposed purpose for life. There are two ways of holding fast to a faith. One way is to stay within the limits of reason and shut down the critical reflection that serves only to undercut that in which you have faith. These are secular confrontations with nihilism . Note that any antidote to nihilism requires shutting down the suicidal critical reflection which serves only to undercut that in which you have faith. The other is to be open to revelation which provides insights which reason could never produce by itself but which we can try to understand with reason even if we can never completely understand them. This is religious confrontation with nihilism. These revealed insights are properly called mysteries.
We get revelations from historical religions. There is a need for subsequent posts to support the thesis that revelation comes only via historical or traditional religions. Acceptance of mysteries involves less intellectual suppression than secularism for we have mysteries to think about.