“It has been an apex of my entire life,” Peter told me, moved, after the Meeting of Rimini two years ago–his last. A world-renowned physicist, an Oxford professor for over half a century, Peter Hodgson criss-crossed the sea, invited to the most prestigious universities in Europe and the States, and engaged in cutting-edge scientific collaborations. He died on December 8th while he was on vacation in South Africa with his wife.
I met him for the first time in Paris in 2002 at a scientific meeting. In a short time, he became a true friend of mine and of many of us. What fortune, what an honor, to have such a friend. The weight of his words was matched by the lightness of his gaze, the serene and profound gaze typical of the great. I‘d been told that he was a committed Christian, that he’d even organized an association of Catholic scientists. Then I discovered that he was also a great man.
He began his career studying the nuclear disintegration caused by cosmic radiation, going on to pursue various studies on the structure of the atomic nucleus and on nuclear reactions. But in addition to being an excellent physicist, Peter was a scholar of great breadth, offering acute and original exploration of the historical roots of scientific knowledge. Drawing upon his vast humanistic and scientific training, Hodgson demonstrated how the particular way of conceiving of and observing nature that we call science had its rational and anthropological premises in the medieval Christian era.

Ordered world. “Science was born just once in history,” he said. I remember our impassioned conversations as together we prepared the Meeting 2005 Euresis exhibit entitled, “On the Shoulders of Giants.” “The reasons are both material and cultural,” he said. As to the first, he emphasized how medieval Europe had reached a certain social development, and had adequate linguistic instruments (writing and mathematics), and how the abbeys and the first medieval universities were places capable of passing on and spreading knowledge. But that’s not all. Other ancient civilizations, for example, in Greece and China, had reached an analogous level of development, and yet science had just a few marvelous surges without ever reaching maturity. Precise cultural premises were needed as well.
In fact, Hodgson underlined, not just any conception of the world, man, and God makes it possible to seriously devote the kind of attention to and inquiry about reality that opens to the experimental method. First of all, there must be the conviction that material reality is worth knowing. This may seem obvious but, really, it isn’t. The vision of the gnostics or epicureans, for example, who preached indifference to the physical world, the knowledge of which was considered useless or dangerous, was incompatible with the birth of science. In addition, it demands the presentiment that the world is ordered, and that this order is accessible to human reason–a mysterious correspondence, Einstein remarked, by which the “most incomprehensible thing about the universe is that it is comprehensible.” It’s not enough to recognize the regularity of the movements of the celestial bodies; you also have to admit the possibility that those movements can be decipherable, at least in part. Finally, it required the persuasion that knowledge of the phenomena and laws of nature is useful for the subject and the human community, even if not immediately so.
Hodgson noted, “The Judeo-Christian conception in the medieval period met for the first time all these prerequisites simultaneously.” In this conception, reality is good and ordered because it was created by a personal and rational God, who freely gives being to realize a good project for creation. The physical world, every single creature or phenomenon, is meaningful inasmuch as it is a sign of the Creator. In addition, the universe is created by God, but it is distinct from Him: creation is the free initiative of the Mystery. “The God of the Jews is very different from the God of Plato or the prime mover of Aristotle…[He] created a world completely distinct from Himself.” In order to know the universe, then, it’s not sufficient to meditate or deduct; you have to go out to meet reality, observe the datum offered by nature. It is in the Judeo-Christian vision that “knowledge is always an adventure,” an encounter with reality.
Realism. But it was precisely the advent of Christianity that marked the decisive cultural turning point. “The Incarnation, the event in which God makes Himself man, ennobles the materiality of reality in an incredible way,” said Hodgson. “From then on, history was no longer an infinite series of cycles, but a linear story with a beginning and an end. A set of beliefs about the world, given by the teaching of Christ, in the end led to the first lively birth of science in the High Middle Ages and its subsequent flowering in the Renaissance.”
 Hodgson was also a witness to and passionate supporter of realism as the condition for a healthy use of reason, and thus also of scientific knowledge. “You can be ignorant of nature for a while,” he said, “but the longer you’re ignorant of it, the more fearsome will be the final rendering of accounts.” In a recent conference in Trieste, he said, “The truth of Christianity, or the truth of atomic theory, or of the heliocentric system, is not based on an individual or some logical arguments; instead, in every case, it rests on an enormous accumulation of personal experiences… [on the] convergence of a vast number of separate indications, none of which is decisive in and of itself.”
 Peter Hodgson had discovered and made his own a broad conception of reason, and so when he encountered the charism of Fr. Giussani he immediately felt at home, so much so that last year in London he enthusiastically accepted the invitation to present The Risk of Education with Fr. Julián Carrón. In Peter, vast knowledge maintained all the boldness of the simple gaze on reality, such that every indication of his seemed to express, implicitly, “how beautiful the world is, and how great God is!

* Professor of Astrophysics at the University of Milan