Many of the Third Orders and lay movements in the Church have a rather simple idea at their core: if one is called to holiness, then one should make use of the “tools” of holiness—i.e. basic Christian practices such as frequent reception of the sacraments, personal prayer, daily reading of the Scriptures, and a life lived in common. These are the practices, the “tools” used by priests and those in the various forms of consecrated life in the Church (the “professionals” of holiness, if you will permit me to stretch the analogy even further). The genius of the ecclesial movements and Third Orders is in the realization that these practices need not be limited to the cloistered or those in positions of Christian leadership. In various degrees and modes, these are practices from which all Christians can benefit.

In this essay, I would like to pursue a parallel line of thought with regard to the more specific topic of evangelization. Though we often fail to realize it, the Church understands evangelization—“the proclamation of Christ by word and testimony of life”—as a participation in Christ’s prophetic office, and thus part of that “universal call to holiness” reaffirmed in Lumen Gentium. Evangelization, like holiness, is not the vocation of a select few. Rather, as St. Thomas Aquinas has written, “To teach in order to lead others to faith is the task of every preacher and of each believer.” If we are baptized Christians, we are evangelists.

I would suggest that just as we can look to the practices of priests and religious to learn some of the “tools” of holiness, we can also look to them to learn some of the “tools” of evangelization. Of course, some of these “tools” or practices are likely to be the same, since personal holiness aids evangelization. However, there is at least one marked difference in the formation of priests compared to most laypeople: priests are required by the Church to study philosophy. To the extent we do the same, we are likely to be better evangelists to our spouses, children, coworkers, and friends—and in some singular cases, even to atheist interviewers on YouTube.

In what ways can the study of philosophy aid in evangelization? Many answers are possible (yes, especially in an article written by a philosopher!), but here I would like to focus upon just three benefits of philosophy: first, philosophy can help us to better understand theology; second, philosophy can enable us to converse intelligently with other people who may not share our faith; and finally, philosophy can help us to achieve a sound understanding of the human person. These three are by no means minor advantages.

The first benefit of philosophy is, as you might say, an internal benefit: it better enables us to personally understand the theology of the Church. Words like substance, accident, person, sign, existence, etc. are originally philosophical terms. They receive a meaning in the context of philosophy, a meaning that gets transformed and adjusted in theology, but never fully disappears. Theology thus builds on philosophy—as the medieval would say, philosophy is theology’s “handmaiden.” This close relationship between the disciplines means that a strong philosophical formation can give one a greater theological aptitude, all other things being equal. And theological aptitude is not merely optional for us as evangelists. While the Holy Spirit sometimes does inspire us with just the right word or turn of phrase when speaking of God to others, in the ordinary course of things grace builds on nature. The Holy Spirit generally works in union with the mind of the evangelist in bearing witness. For the evangelist to totally ignore philosophical formation is thus a sort of silent arrogance, a presumption that the Holy Spirit will perform at our beck and call to make up for what we lack.

The second great benefit of philosophy is more of an external benefit: philosophy equips us to speak about God, religion, mankind, and other important subjects with those who do not share our faith. One might be tempted to think that the Sacred Scriptures always equip us well for such conversations, but in many cases they do not. As I often remind my students, the argument from authority is one of the strongest arguments in theology (or the strongest, if the authority in question is God), yet such arguments can be weak in other contexts. When speaking to our fellow Christians, it is appropriate to draw upon the Sacred Scriptures. We accept such texts as true because of the authority of their author, God himself. Yet we are likely to be far less effective in convincing unbelievers, or those of a different faith, by citing verses from the Scriptures. For such people, there is no guarantee of the veracity of these texts, since they do not yet accept the authority behind them. By contrast, a more philosophical approach does not fall victim to this problem. Philosophical arguments do not depend upon any authority other than human reason, something we share with our fellow humans. Philosophical considerations are therefore well-suited to serve as “preambles to the faith.”

A third benefit of philosophy—and perhaps the greatest, given the current cultural milieu in the West—is that philosophy can help us to achieve an “adequate anthropology,” a correct view of the human person. I realize that this assertion may sound surprising to some, for we are used to thinking of philosophy in terms of its caricature as endless argument over minute matters. Yet its “argumentative” nature of philosophy is actually a clue to its importance, for argument presupposes truth. We do not argue seriously over matters of personal taste: we argue over matters of objective truth. A deep and serious study of philosophy thus helps one, bit by bit, to see clear of the current cultural fog of what is sometimes called “cognitive relativism,” the idea that truth is whatever I decide it is—whether it is the truth of one’s words, one’s sexuality, or one’s marital status. We really have not understood the human person at all until St. Augustine and other philosophers help to cement this fundamental idea in place for us: as creatures, we are judged by the truth; we are not its judges.