Pope Francis' first encyclical, "Light of Faith" (Lumen fidei), is certainly the easiest-to-read papal writing in recent years. Gone is the fake parchment background typical of the Vatican website -- impressive maybe the first time you saw it, but stale and an obstacle to reading ever since. This document is visible in a crisp sans serif font against a pure white background. And it can easily be downloaded in an elegantly formatted PDF, which concedes nothing to the best printed versions of former encyclicals.

Such clarity is appropriate for an encyclical which is primarily interested in emphasizing how faith illuminates. Please allow this to sink in: faith sheds light; it assists us in seeing; it helps us see truth and especially the most important truths. Many of these truths, too, are important "common goods" for life together in the family and in the society.

We can get clearer about the theme of the encyclical by stating what it rejects. The Holy Father rejects, and teaches us to reject, the view that faith is a deliberate obscurity of the mind, which was suited perhaps to past "Dark Ages," but which has been rightly pushed aside by an "Enlightenment Age" in favor of a supposedly "autonomous" human reason. Or that faith is a matter of entering or constructing a purely private world -- "defining one's own concept of existence, of meaning, of the universe, and of the mystery of life" (in the phrase of Justice Kennedy). Or that faith is a comforting emotion, a feeling, or a bias, yet which lacks a basis in truth.

If you want to be old-fashioned, then go ahead and find a quiet room where you can read these false views aloud and declare "Anathema sit!" after each one -- which I agree could be therapeutic -- though keep in mind that the imperative of dialogue with those who lack faith, emphasized too in the encyclical (which is sometimes also a dialogue with oneself), will not thereby go away.

What then is faith, according to the encyclical? It is an insight into the truth, which involves not simply seeing, but also something like attentiveness in hearing, and even confirmation in something like touching. If the intellect is most analogous to sight, there are respects in which, tellingly, faith is like each of the senses (even smell: think of St. Paul's reference to the 'odor' or 'scent' of Christ). Faith originates in love and is a matter of the heart. Like life, it is a gift from God which is meant to be shared, and which gains vitality through its being transmitted.

Faith helps us to see new things (like the truth of the Trinity), and old things in a new light (such as, say, the classical view of human dignity), and to see things which we might had a chance of seeing on our own but most probably wouldn't have (such as that life is a gift, or that the common good has priority over my personal good). It is a great light which brightens other lights, including the light of reason.

Faith and reason are meant to assist each other to arrive at truth. Pope Francis refers to that marvelous image of Blessed John Paul II, that faith and reason are the like two wings of a bird. In this task, faith is not dispensable. We might trick ourselves into supposing that it is, when some truth formerly gained with the help of faith has been so written into habit, or embodied in an institution, or implicitly accepted by a culture, that we forget its source and imagine that it is our own creation and possession. Yet even then we find that this truth can lose its salience, become mechanical, or even be lost altogether, unless we continue to recommit ourselves to it in faith. With reason alone we cannot be true to ourselves or to what we take our "reason" alone to be.

Consider, as an example, the famous words from the Declaration of Independence, "we hold these truths to be self-evident, that all men are created equal and endowed by their Creator with inalienable rights." Are they self-evident to reason alone, or to reason as itself illuminated with the light of faith? I grant that when we "see" them, we do see them reasonably, and with reason. But do we all see them? If we saw them by "reason alone," then it presumably would be the case that someone would need only reason, and then straightaway he or she would see them, and so all of us would see them. And yet this is manifestly not so. As Abraham Lincoln pointed out, some of his political opponents agreed with Senator Pettit of Indiana that human equality was, rather, a "self-evident lie". Today, the evident truth of God's existence is not seen by some and is surely not "self-evident" to them. Today, legal abortion, just as slavery and segregation in earlier generations, shows we hardly "see" with reason alone the truth of human equality -- although, again, when we do see it, we see it reasonably and with reason.

The Holy Father reminds us that we need faith to see most truths which serve as common goods undergirding civilization -- that a permanent commitment between man and woman is possible; that children are a good; that humanity is a family under a single heavenly Father; indeed, that truth itself is attainable.

Michael Pakaluk is Chairman and Professor of Philosophy at Ave Maria University. He blogs at MichaelPakaluk.com.