by Isaac Asimov
Rubin's sparse beard seemed to stiffen, and he said, “Oh, that's a lot of junk, Roger. That sort of reasoning should make thirteen a lucky number. Any tradesman would offer to throw in the thirteenth to sweeten the trade. —That's good steak, Henry.”
“Baker's dozen,” said James Drake in his hoarse smoker's voice.
“The baker,” said Avalon, “threw in a thirteenth loaf to make up a baker's dozen in order to avoid the harsh penalties meted out for short weight. By adding the thirteenth, he was sure to go over weight even if any of the normal twelve loaves were skimpy. He might consider the necessity to be unlucky.”
“The customer might consider it lucky,” muttered Rubin.
“As for Friday,” said Halsted, “that is named for the goddess of love, Freya in the Norse myths. In the Romance languages the name of the day is derived from Venus; it is vendredi in French, for instance. I should think it would be considered a lucky day for that reason. Now you take Saturday, named for the dour old god, Saturn—”
Gonzalo had completed his caricature and passed it around the table to general approval and to a snicker from Fletcher himself. He seized the opportunity to finish his potato puffs and said, “All you guys are trying to reason out something that lies beyond reason. The fact is that people are afraid of Friday and are afraid of thirteen and are especially afraid of the combination. The fear itself could make bad things happen. I might be so concerned that this place will catch fire, for instance, because it's Friday the thirteenth, that I won't be thinking and I'll stick my fork in my cheek.”
“If that would shut you up, it might be a good idea,” said Avalon.
“But I won't,” said Gonzalo, “because I have my eye on my fork and I know that Henry will get us all out if the place catches on fire, even if it means staying behind himself and dying in agony. —Right, Henry?”
“I hope that the contingency will not arise, sir,” said Henry, placing the dessert dishes dexterously before each diner. “Will you be having coffee, sir?” he asked Fletcher.
“May I have cocoa? Is that possible?” said Fletcher.
“Certainly it is,” interposed Avalon. “Go, Henry, negotiate the matter with the chef.”
And it was not long thereafter, with the coffee (or cocoa, in Fletcher's case) steaming welcomely before them, that Avalon tapped his water glass with his spoon and said, “Gentlemen, it is time to turn our attention to our guest. Tom, will you initiate the matter?”
Trumbull put down his coffee cup, scowled his face into a cross-current of wrinkles, and said, “Ordinarily, Dr. Fletcher, I would ask you to justify your existence, but having sat through an extraordinarily foolish discussion of superstition, I want to ask you whether you have anything to add to the matter. You implied early in the meal that you would have raised the matter of Friday the thirteenth yourself if it had not come up otherwise.”
“Yes,” said Fletcher, holding his large ceramic cup of cocoa within the parentheses of his two hands, “but not as a matter of superstition. Rather it is a serious historic puzzle that concerns me and that hinges on Friday the thirteenth. Jeff said that the Black Widowers were fond of puzzles and this is the only one I have for you—with the warning, I'm afraid, that there is no solution.”
“As you all know,” said Avalon, with resignation, 'Tm against turning the club into a puzzle-solving organization, but I seem to be a minority of one in this matter, so I try to go along with the consensus.” He accepted the small brandy glass from Henry with a look compounded of virtue and martyrdom.
“May we have this puzzle?” said Halsted.
“Yes, of course. I thought for a moment, when Jeff invited me to attend your dinner, that it was to be held on Friday the thirteenth in my honor, but that was a flash of megalomania. I understand that you always hold your dinners on a Friday evening and, of course, no one knows about my work but myself and my immediate family.”
He paused to light his pipe, then, leaning back and puffing gently, he said, 'The story concerns Joseph Hennessy, who was executed in 1925 for an attempt on the life of President Coolidge.* He was tried on this charge, convicted, and hanged.
'To the end, Hennessy.[1] proclaimed his innocence and advanced a rather strong defense, with a number of people giving evidence for his absence from the scene. However, the emotional currents against him were strong. He was an outspoken labor leader, and a Socialist, at a time when fear of Socialism ran high. He was foreign-born, which didn't help. And those who gave evidence in his favor were also foreign-born Socialists. The trial was a travesty and, once he was hanged and passions had time to cool, many people realized this.
“After the execution, however, long after, a letter was produced in Hennessy's handwriting that seemed to make him a moving figure behind the assassination plot beyond a doubt. This was seized on by all those who had been anxious to see him hanged, and it was used to justify the verdict. Without the letter, the verdict must still be seen as a miscarriage of justice.”
Drake squinted from behind the curling smoke of his cigarette and said, “Was the letter a forgery?”
“No. Naturally, those who felt Hennessy was innocent thought it was at first. The closest study, however, seemed to show that it was indeed in his handwriting, and there were things about it that seemed to mark it his. He was a grandiosely superstitious man, and the note was dated Friday the thirteenth and nothing more.”
“Why 'grandiosely' superstitious?” asked Trumbull. “That's an odd adjective to use.”
“He was a grandiose man,” said Fletcher, “given to doing everything in a flamboyant manner. He researched his superstitions. In fact, the discussion at the table as to the significance of Friday and of thirteen reminded me of the sort of man he was. He probably would have known more about the matter than any of you.”
“I should think,” said Avalon gravely, “that investigating superstitions would militate against his being victimized by them.”
“Not necessarily,” said Fletcher. “I have a good friend who drives a car frequently but won't take a plane because he's afraid of them. He has heard all the statistics that show that on a man-mile basis airplane travel is safest and automobile travel most dangerous, and when I reminded him of that, he replied, 'There is nothing either in law or in psychology that commands me to be rational at every point.' And yet in most things he is the most rational man I know.
“As for Joe Hennessy, he was far from an entirely rational man and none of his careful studies of superstition prevented him in the least from being victimized by them. And his fear of Friday the thirteenth was, perhaps, the strongest of all his superstitious fears.”
Halsted said, “What did the note say? Do you remember?”
“I brought a copy,” said Fletcher. “It's not the original, of course. The original is in the Secret Service files, but in these days of Xeroxing, that scarcely matters.”
He took a slip of paper out of his wallet and passed it to Halsted, who sat on his right. It made the rounds of the table and Avalon, who received it last, automatically passed it to Henry, who was standing at the sideboard. Henry read it with an impassive countenance and handed it back to Fletcher, who seemed slightly surprised at having the waiter take part, but said nothing.
The note, in a bold and easily legible handwriting, read:
Friday the 13th Dear Paddy,
It's a fool I am to be writing you this day when I should be in bed in a dark room by rights. I must tell you, though, the plans are now completed and I dare not wait a day to begin implementing them. The finger of God has touched that wicked man and we will surely finish the job next month. You know what you must do, and it must be done even at the cost of every drop of blood in our veins. I thank God's mercy for the forty-year miracle that will give us no Friday the 13th next month.
Joe
Avalon said, “He doesn't really say anything.”
Fletcher shook his head. “On the contrary, he says too much. If this were the prelude to an assassination
attempt, would he have placed anything at all in writing? Or if he had, would the reference not have been much more dark and Aesopic?”
“What did the prosecution say it meant?”
Fletcher put the note carefully back into his wallet. “As I told you, the prosecution never saw it The note was uncovered only some ten years after the hanging, when Patrick Reilly, to whom the note was addressed, died and left it among his effects. Reilly was not implicated in the assassination attempt, though of course he would have been if the note had come to light soon enough.
“Those who maintain that Hennessy was rightly executed say that the note was written on Friday, June 13, 1924. The assassination attempt was carried through on Friday, July 11, 1924. It would have made Hennessy nervous to have made the attempt on any Friday, but for various reasons involving the presidential schedule that was the only possible day for a considerable period of time, and Hennessy would be understandably grateful that it was not the thirteenth at least.
'The remark concerning the finger of God touching the wicked man is said to be a reference to the death of President Warren G. Harding, who died suddenly on August 2, 1923, less than a year before the assassination attempt was to 'finish the job' by getting rid of the Vice-President who had succeeded to the presidency.”
Drake, with his head cocked to one side, said, “It sounds like a reasonable interpretation. It seems to fit.”
“No, it doesn't,” said Fletcher. “The interpretation is accepted only because anything else would highlight a miscarriage of justice. But to me—” He paused and said, “Gentlemen, I will not pretend to be free of bias. My wife is Joseph Hennessy's granddaughter. But if the relationship exposes me to bias, it also gives me considerable personal information concerning Hennessy by way of my father-in-law, now dead.
“Hennessy had no strong feelings against either Harding or Coolidge. He was not for them, of course, for he was a fiery Socialist, supporting Eugene Debs all the way—and that didn't help him at the trial, by the way. There was no way in which he could feel that the assassination of Coolidge would have accomplished anything at all. Nor would he have felt Harding to be a ‘wicked man' since the evidence concerning the vast corruption that had taken place during his administration came to light only gradually, and the worst of it well after the note was written.
“In fact, if there was a President whom Hennessy hated furiously, it was Woodrow Wilson. Hennessy had been born in Ireland and had left the land a step ahead of English bayonets. He was furiously anti-British and therefore, in the course of World War I, was an emphatic pacifist, opposing American entry on the side of Great Britain. —That didn't help him at the trial either.”
Rubin interposed, “Debs opposed entry also, didn't he?”
“That's right,” said Fletcher, “and in 1918 Debs was jailed as a spy in consequence. Hennessy avoided prison, but he never referred to Wilson after American entry into war by any term other than that wicked man.' He had voted for Wilson in 1916 as a result of the 'He-kept-us-out-of-war' campaign slogan, and he felt betrayed, you understand, when the United States went to war the next year.”
“Then you think he's referring to Wilson in that note,” said Trumbull.
“I'm sure of it. The reference to the finger of God touching the wicked man doesn't sound like death to me, but something else—just the touch of the finger, you see. As you probably all know, Wilson suffered a stroke on October 2, 1919, and was incapacitated for the remainder of his term. That was the finger of God, if you like.”
Gonzalo said, “Are you saying Hennessy was going to finish the job by assassinating Wilson?”
“No, no, there was no assassination attempt on Wilson.”
“Then what does he mean, 'finish the job,' and doing it even at the cost of every drop of blood in our veins'?”
“That was his flamboyance,” said Fletcher. “If he was going out for a bucket of beer he would say, I’ll bring it back if it costs me every drop of blood in my veins.'“
Avalon leaned back in his chair, twirled his empty brandy glass, and said, “I don't blame you, Evan, for wanting to clear your grandfather-in-law, but you'll need something better than what you've given us. If you can find another Friday the thirteenth on which the letter could have been written, if you can figure out some way of pinpointing the date to something other than June 13, 1924—”
“I realize that,” said Fletcher, rather glumly, “and I’ve gone through his life. I've worked with his correspondence and with newspaper files and with my father-in-law's memory, until I think I could put my finger on where he was and what he did virtually every day of his life. I tried to find events that could be related to some nearby Friday the thirteenth, and I even think I've found some—but how do I go about, proving that any of them are the Friday the thirteenth? —If only he had been less obsessed by the fact of Friday the thirteenth and had dated the letter in the proper fashion.”
“It wouldn't have saved his life,” said Gonzalo thoughtfully.
“The letter couldn't then have been used to besmirch his memory and give rise to the pretense that the trial was fair. —As it is, I don't even* know that I've caught every Friday the thirteenth there might be. The calendar is so dreadfully irregular that there's no way of knowing when the date will spring out at you.”
“Oh no,” said Halsted with a sudden soft explosiveness. “The calendar is irregular, but not as irregular as all that. You can find every Friday the thirteenth without trouble as far back or as far forward as you want to go.”
“You can?” said Fletcher with some astonishment.
“I don't believe that,” said Gonzalo, almost simultaneously.
“It's very easy,” said Halsted, drawing a ball-point pen out of his inner jacket pocket and opening a napkin on the table before him.
“Oh, no,” said Rubin, in mock terror. “Roger teaches math at a junior high school, Dr. Fletcher, and you had better be ready for some complicated equations.”
“No equations at all necessary,” said Halsted loftily. “I'll bring it down to your level, Manny. —Look, there are 365 days in a year, which comes out to fifty-two weeks and one day. If the year were 364 days long, it would be just fifty-two weeks long, and the calendar would repeat itself each year. If January 1 were on a Sunday one year, it would be on a Sunday the next year and every year.
“That extra day, however, means that each year the weekday on which a particular date falls is shoved ahead by one. If January 1 is on a Sunday one year, it will fall on Monday the next year, and on Tuesday the year after.
“The only complication is that every four years we have a leap year in which a February 29 is added, making 366 days in all. That comes to fifty-two weeks and two days, so that a particular date is shoved ahead by two in the list of weekdays. It leaps over one, so to speak, to land on the second, which is why it is called leap year. That means that if January 1 falls on, say, a Wednesday in leap year, then the next year January 1 falls on a Friday, having leaped over the Thursday. And this goes for any day of the year and not just January 1.
“Of course, February 29 comes after two months of a year have passed so that dates in January and February make their leap the year after leap year, while the remaining months make their leap in leap year itself. In order to avoid that complication, let's pretend that the year begins on March 1 of the year before the calendar year and ends on February 28 of the calendar year—or February 29 in leap year. In that way, we can arrange to have every date leap the weekday in the year after what we call leap year.
“Now let's imagine that the thirteenth of some month falls on a Friday—it doesn't matter which month—and that it happens to be a leap year. The date leaps and lands on Sunday the next year. That next year is a normal 365-day year and so are the two following, so the thirteenth progresses to Monday, Tuesday, and Wednesday, but the year in which it is Wednesday is a leap year again and the next year it falls on a Friday. In other words, if the thirteenth of some months is on a Friday
of leap year, by our definition, then it is on a Friday again five years later—” Gonzalo said, 'I’m not following you at all.” Halsted said, “Okay, then, let's make a table. We can list the years as L, 1, 2, 3, L, 1, 2, 3 and so on where L stands for leap year, coming every four years. We can label the days of the week from A to G, A for Sunday, B for Monday through to G for Saturday. That will, at least, give us the pattern. Here it is—”
He scribbled furiously, then passed the napkin round. On it was written:
L123L123L123L123 ACDEFABCDFGABDEF
L123L123L123L GBCDEGABCEFGA
“You see,' said Halsted, “on the twenty-ninth year after you start, A falls on leap year again and the whole pattern starts over. That means that this year's calendar can be used again twenty-eight years from now and then again twenty-eight years after that, and twenty-eight years after that, and so on.
“Notice that each letter occurs four times in the twenty-eight-year cycle, which means that any date can fall on any day of the week with equal probability. That means that Friday the thirteenth must come every seven months on the average. Actually, it doesn't because the months are of different lengths, irregularly spaced, so that there can be any number of Friday the thirteenths in any given year from 1 to 3. It is impossible to have a year with no Friday the thirteenths at all, and equally impossible to have more than three.”
“Why is there a twenty-eight-year cycle?” asked Gonzalo.
Halsted said, “There are seven days in the week and a leap year every fourth year and seven times four is twenty-eight.”
“You mean that if there were a leap year every two years the cycle would last fourteen years?”
“That's right, and if it were every three years it would last twenty-one years and so on. As long as there are seven days a week and a leap year every x years, with x and 7 mutually prime—”
