“As far as simple people are concerned, my only fear is that they may be terrified by them, confusing them with those works of the Devil of which their preachers speak too often. You see, I have happened to know very skilled physicians who had distilled medicines capable of curing a disease immediately. But when they gave their unguent or their infusion to the simple, they accompanied it with holy words and chanted phrases that sounded like prayers: not because these prayers had the power to heal, but because, believing that the cure came from the prayers, the simple would swallow the infusion or cover themselves with the unguent, and so they would be cured, while paying little attention to the effective power of the medicine. Also, the spirit, aroused by faith in the pious formula, would be better prepared for the corporal action of the medication. But often the treasures of learning must be defended, not against the simple but, rather, against other learned men. Wondrous machines are now made, of which I shall speak to you one day, with which the course of nature can truly be predicted. But woe if they should fall into the hands of men who would use them to extend their earthly power and satisfy their craving for possession. I am told that in Cathay a sage has compounded a powder that, on contact with fire, can produce a great rumble and a great flame, destroying everything for many yards around. A wondrous device, if it were used to shift the beds of streams or shatter rock when ground is being broken for cultivation. But if someone were to use it to bring harm to his personal enemies?”

“Perhaps it would be good, if they were enemies of the people of God,” Nicholas said piously.

“Perhaps,” William admitted. “But who today is the enemy of the people of God? Louis the Emperor or John the Pope?”

“Oh, my Lord!” Nicholas said, quite frightened. “I really wouldn’t like to decide such a painful question!”

“You see?” William said. “Sometimes it is better for certain secrets to remain veiled by arcane words. The secrets of nature are not transmitted on skins of goat or sheep. Aristotle says in the book of secrets that communicating too many arcana of nature and art breaks a celestial seal and many evils can ensue. Which does not mean that secrets must not be revealed, but that the learned must decide when and how.”

“Wherefore it is best that in places like this,” Nicholas said, “not all books be within the reach of all.”

“This is another question,” William said. “Excess of loquacity can be a sin, and so can excess of reticence. I didn’t mean that it is necessary to conceal the sources of knowledge. On the contrary, this seems to me a great evil. I meant that, since these are arcana from which both good and evil can derive, the learned man has the right and the duty to use an obscure language, comprehensible only to his fellows. The life of learning is difficult, and it is difficult to distinguish good from evil. And often the learned men of our time are only dwarfs on the shoulders of dwarfs.”

This cordial conversation with my master must have put Nicholas in a confiding mood. For he winked at William (as if to say: You and I understand each other because we speak of the same things) and he hinted: “But over there”—he nodded toward the Aedificium—”the secrets of learning are well defended by works of magic….”

“Really?” William said, with a show of indifference. “Barred doors, stern prohibitions, threats, I suppose.”

“Oh, no. More than that…”

“What, for example?”

“Well, I don’t know exactly; I am concerned with glass, not books. But in the abbey there are rumors … strange rumors….”

“Of what sort?”

“Strange. Let us say, rumors about a monk who decided to venture into the library during the night, to look for something Malachi had refused to give him, and he saw serpents, headless men, and men with two heads. He was nearly crazy when he emerged from the labyrinth….”

“Why do you speak of magic rather than diabolical apparitions?”

“Because even if I am only a poor master glazier I am not so ignorant. The Devil (God save us!) does not tempt a monk with serpents and two-headed men. If anything, with lascivious visions, as he tempted the fathers in the desert. And besides, if it is evil to handle certain books, why would the Devil distract a monk from committing evil?”

“That seems to me a good enthymeme,” my master admitted.

“And finally, when I was repairing the windows of the infirmary, I amused myself by leafing through some of Severinus’s books. There was a book of secrets written, I believe, by Albertus Magnus; I was attracted by some curious illustrations, and I read some pages about how you can grease the wick of an oil lamp, and the fumes produced then provoke visions. You must have noticed—or, rather, you cannot have noticed yet, because you have not yet spent a night in the abbey—that during the hours of darkness the upper floor of the Aedificium is illuminated. At certain points there is a dim glow from the windows. Many have wondered what it is, and there has been talk of will-o’-the-wisps, or souls of dead librarians who return to visit their realm. Many here believe these tales. I think those are lamps prepared for visions. You know, if you take the wax from a dog’s ear and grease a wick, anyone breathing the smoke of that lamp will believe he has a dog’s head, and if he is with someone else, the other will see a dog’s head. And there is another unguent that makes those near the lamp feel big as elephants. And with the eyes of a bat and of two fish whose names I cannot recall, and the venom of a wolf, you make a wick that, as it burns, will cause you to see the animals whose fat you have taken. And with a lizard’s tail you make everything around you seem of silver, and with the fat of a black snake and a scrap of a shroud, the room will appear filled with serpents. I know this. Someone in the library is very clever….”

“But couldn’t it be the souls of the dead librarians who perform these feats of magic?”

Nicholas remained puzzled and uneasy. “I hadn’t thought of that. Perhaps. God protect us. It’s late. Vespers have already begun. Farewell.” And he headed for the church.

We continued along the south side: to our right the hospice for pilgrims and the chapter house with its gardens, to the left the olive presses, the mill, the granaries, the cellars, the novices’ house. And everyone was hurrying toward the church.

“What do you think of what Nicholas said?” I asked.

“I don’t know. There is something in the library, and I don’t believe it is the souls of dead librarians….”

“Why not?”

“Because I imagine they were so virtuous that today they remain in the kingdom of heaven to contemplate the divine countenance, if this answer will satisfy you. As for the lamps, we shall see if they are there. And as for the unguents our glazier spoke of, there are easier ways to provoke visions, and Severinus knows them very well, as you realized today. What is certain is that in the abbey they want no one to enter the library at night and that many, on the contrary, have tried or are trying to do so.”

“And what does our crime have to do with this business?”

“Crime. The more I think about it, the more I am convinced that Adelmo killed himself.”

“Why is that?”

“You remember this morning when I remarked the heap of dirty straw? As we were climbing up the curve beneath the east tower I had noticed at that point the traces left by a landslide: or, rather, a part of the terrain had given way below the tower, more or less there where the waste collects, and had slipped. And that is why this evening, when we looked down from above, the straw seemed to have little snow covering it; it was covered only by the latest fall, yesterday’s snow, and not by that of the past few days. As for Adelmo’s corpse, the abbot told us that it had been lacerated by the rocks, and beneath the east tower, where the building joins a sheer drop, there are pines growing. The rocks, however, are directly under the point where the wall ends, forming a kind of step, and afterward the straw dump begins.”

“And so?”

“And so, think whether it is not less—how shall I say it?—less costly for our minds to believe that Adelmo, for reasons yet to be ascertained, threw himself of his own will from the parapet of the wall, struck the rocks, and, dead or wounded as he may have been, sank into the straw. Then the landslide, caused by the storm that night, carried the straw and part of the terrain and the poor young man’s body down below the east tower.”

“Why do you say this solution is less costly for our minds?”

“Dear Adso, one should not multiply explanations and causes unless it is strictly necessary. If Adelmo fell from the east tower, he must have got into the library, someone must have first struck him so he would offer no resistance, and then this person must have found a way of climbing up to the window with a lifeless body on his back, opening it, and pitching the hapless monk down. But with my hypothesis we need only Adelmo, his decision, and a shift of some land. Everything is explained, using a smaller number of causes.”

“But why would he have killed himself?”

“But why would anyone have killed him? In either case reasons have to be found. And it seems to me beyond doubt that they existed. In the Aedificium there is an atmosphere of reticence; they are all keeping something quiet. Meanwhile, we have already collected a few insinuations—quite vague, to be sure—about some strange relationship between Adelmo and Berengar. That means we will keep an eye on the assistant librarian.”

While we were talking in this fashion, the office of vespers ended. The servants were going back to their tasks before retiring for supper, the monks were heading for the refectory. The sky was now dark and it was beginning to snow. A light snow, in soft little flakes, which must have continued, I believe, for most of the night, because the next morning all the grounds were covered with a white blanket, as I shall tell.

I was hungry and welcomed with relief the idea of going to table.