''Fratelli Tutti," the pope's recent encyclical, presents an outlook and advocates policies to foster friendship among the entire human family. Friendship is not possible if the inequalities among us are too great -- even Aristotle made this point. Moreover, we cannot be friends with those we exclude and ignore. Therefore, the focus of the encyclical is rightly on practices that foster equality and inclusion.

The encyclical makes the excellent point that, as COVID has effectively put the frenzy of daily business on hold, we have a certain freedom to evaluate our desires and practices of consumption. We would have lost a great opportunity to convert if, after the lockdowns, we return simply to the "status quo ante."

The basis for social friendship among the human family, the pope teaches, is the truth of the human person as made in the image of the Father God. "With God as Our Father, brothers all are we," the song goes, and the encyclical, too.

It is true that, at one point, the encyclical surmises that its teachings might be available to agnostics as well. But -- and commentators have generally missed this -- overall, it rejects the premise that social friendship can effectively be fostered other than within a monotheistic worldview of faith. Although the pope is beloved of many secularists, he firmly rejects secularism as a viable framework for the reforms he favors.

Indeed, secularism is clearly inadequate for friendship within the human family. Our secular universities, in their particular positive sciences, do not even recognize such a thing as human nature. They give us fragmentation. Actually, they tamper with human nature now, through genetic manipulation and human-animal hybrids.

Nor is an insight into the human family, as having a shared nature and (as it were) essence, fostered within the humanities, as they are taught in secular universities. We cannot expect human nature to be seen and defended by those who deny the very complementarity of male and female. The only thing standing between us and the Abolition of Man (see C. S. Lewis) is robust faith in God. This the encyclical constantly asserts in its presuppositions.

Of course secularism, too, has given us Roe v. Wade, the Supreme Court decision legalizing abortion throughout all nine months of pregnancy. Legal abortion is the practical denial that man is made in the image of God and possesses inherent dignity. If the unborn child is nothing but a blob of cells, then you and I, too, are nothing but blobs of cells. Additional growth, a mere change in size, will never convert any blob of cells into a son or daughter of God.

Furthermore, legal abortion is the practical denial that we possess the "right to life" (= the dignity of the human person) just because we are human. If we possess this because we are human, then the unborn child, too, possesses it, because even at the earliest stages it is human and shares human nature with us. Put another way, if abortion is licit, then there is no shared human nature and no human family. Indeed, war rather than friendship marks human relationships, if a woman is often at odds with her own offspring.

It follows that secularism is bankrupt as a source of human fraternity. But how does one proclaim this truth? Or, rather, how does a pope proclaim it who has made it clear that our beliefs are shown in how we act more than what we say?

The problem, as it were, is that the Catholic Church pursues the so-called "apostolate of like by like," (called the apostolate of "accompaniment" by Pope Francis), and, thus, its activities throughout the world are largely hidden, like yeast in a loaf. Catholicism in its laity is a religion which embraces a kind of "secularity." That it is a religion which, at the same time, is at odds with secularism, then, even in its social teaching, might at first be unclear.

Yet there can be no doubt that St. Francis rejected secularism -- for him, even inanimate creatures were as if "brother" and "sister" before God. And there can be no doubt that Muslims reject secularism.

Therefore, it is significant -- it is a "sign" of the message of the encyclical -- that it was published in Assisi near to the feast of St. Francis, and that the pope says explicitly that many of the teachings in the encyclical were inspired by his close collaboration with a leading Muslim cleric.

It is the Grand Imam Ahmad Al-Tayyeb, not Jeffrey Sachs, who is cited as the kindred spirit of "Fratelli Tutti."

Remember what Vatican II taught, in its decree on other religions? "The Church regards with esteem also the Moslems. They adore the one God, living and subsisting in Himself; merciful and all- powerful, the Creator of heaven and earth, who has spoken to men; they take pains to submit wholeheartedly to even His inscrutable decrees, just as Abraham, with whom the faith of Islam takes pleasure in linking itself, submitted to God."

Pope Francis, once again, professes that this is so, not so much by what he explicitly says, but rather by how he acts. Now, in that passage, consider the words beginning "They adore the one God...." These give something like Vatican II's assessment of the common ground between Christians and Muslims.

But they also give the framework for human fraternity in "Fratelli Tutti."

- Michael Pakaluk, an Aristotle scholar and Ordinarius of the Pontifical Academy of St. Thomas Aquinas, is a professor in the Busch School of Business at the Catholic University of America. He lives in Hyattsville, MD, with his wife Catherine, also a professor at the Busch School, and their eight children. His latest book, on the Gospel of Mark, is "The Memoirs of St Peter." His next book,"Mary's Voice in the Gospel of John," is forthcoming from Regnery Gateway.