The Science of the Heart
Apr 18, 2025News
Born in 1638, Nicolas Steno was first a scientist, and then a convert, and finally a priest. In 1988, he was beatified by Pope Saint John Paul II. Steno’s accomplishments are numerous, from the foundation of the sciences of stratigraphy and geology to his Counter-Reformation evangelization among the Protestant friends of his youth.
Blessed Nicolas Steno was born in the city of Copenhagen, Denmark. His parents were Lutherans, and his father worked as a goldsmith. Steno grew up isolated until, at the age of 19, he went to the University of Copenhagen to study medicine. By the time he had finished these studies, he was ready to embark on the travels which would carry him to the end of his life. His post-graduate studies took him all across Europe, and he learned from many prominent scientists. His studies were especially effective in the field of anatomy, where he made a number of important discoveries, including the nature of the heart as a muscle and the stable volume of muscles during expansion and contraction.
These studies of anatomy earned him, in 1666, the commission to dissect an enormous, recently discovered shark’s head. The nature of the shark’s tooth, with its layers of various materials, drew him to the study of the formation of solids within other solids. His studies here would prove foundational to the sciences of both geology and stratigraphy (the latter being the study of rock layers and their arrangement), both of which take core tenets from Steno’s work.
Traveling across Europe, Steno eventually found himself in Florence, Italy. His naturally inquisitive mind and scientific training had already led him to question the faith of his youth, and in Florence, he was confronted with a predominantly Catholic culture. After comparing the two religions in study and examining the Church Fathers, Steno realized the truth, and joined the Church on All Souls Day of 1667. He continued his theological studies until, 350 years ago this week, he was ordained a priest.
Working hard as a priest, Steno continued to apply his mind to theology, and his efforts in the Counter-Reformation earned him a bishopric. As a bishop Steno lived an austere life, following ascetic principles and giving the vast majority of his money to the poor. He continued his missionary work as well, taking positions in various Protestant dominated areas. He finally died in 1686, at the age of 48.
Nicolas Steno was beatified by Pope Saint John Paul II, who said of him, “If he is famous for the discoveries made in the field of anatomy, more important is what he shows us with his life choices. . . . through the ‘science of the heart’ [he] found God, the Creator of all that exists and Savior of the world.”
In Steno’s life and works, we see a profound understanding of the relationship of Faith and reason, of the natural and the supernatural. Each pair lived in harmony in him, just as they should in all of us.
Steno’s road to conversion began in his love of the natural sciences. He looked at the world, and saw its Creator reflected in it. As he himself said in his Ad Novae Philosophiae Reformatorem de Vera Philosophia Epistola, “The same eternal wisdom reveals itself both in nature and in revelation.” He saw the eternal wisdom revealed in nature and followed it to the fullness of truth in the Church. Indeed, the natural, when followed up to its heights, seems always to lead us to the supernatural, just as when we ascend to the highest places of the earth, we see the stars most clearly.
The movement of Steno from the lower to higher good is also reflected in his actions. Prior to his conversion, he seems to have been a man who sought to follow the natural law. Following his conversion, however, he quickly became a shining example of supernatural virtue. His severely ascetic lifestyle, generous almsgiving, and missionary work among his former friends all indicate this. Using Steno’s own words regarding natural and supernatural virtue, we can say of him that he went from being one of those men who “seek after truth and righteousness by the light of natural reason” to being “transformed from within, not only in knowledge but in desire.”
His reason followed the same path, with his serious study of theology following his conversion. His missionary work would have required a deep knowledge of theology, and indeed theology was part of what first helped draw him into the church. The transition from seeking the knowledge which belongs to the world to that which belongs to Christ mirrored his own change from sinner to saint, from heresy to orthodoxy.
Steno’s life reminds us of what his words tell us: “Although philosophers may speculate on perfect wisdom, the saints live it.” Let us all strive to live that perfect wisdom this Holy Week, the wisdom of Christ. It will guide us no matter our vocation, no matter our place, no matter our field of study. Christ died for all today, and we look forward to his Resurrection on Sunday.
