Each year, another New Year's Day falls upon us; and because my birthday follows hard upon New Year's Day, the beginning of the year is always a doubled occasion for great and somber soul-searching on my part.

Perhaps I can make my consciousness of passing time less poignant by thinking more objectively. For instance, who says the year starts on New Year's Day? What is there about New Year's Day that is different from any other day? What makes January I so special?

In fact, when we chop up time into any kind of units, how do we decide with which unit to start?

For instance, let's begin at the beginning (as I dearly love to do) and consider the day itself.

The day is composed of two parts, the daytime* and the night. Each, separately, has a natural astronomic beginning. The daytime begins with sunrise; the night be gins with sunset. (Dawn and twilight encroach upon the night but that is a mere detail.)

In the latitudes in which most of humanity live' how ever, both daytime and night change in length during the year (one growing longer as the other grows shorter) and there is, therefore, a certain convenience in using daytime plus night as a single twenty-four-hour unit of time. The combination of the two, the day, is of nearly constant duration.

It is very annoying that "day" means both the sunlit portion of time and the twenty-four-hour period of daytime and night together. This is a completely unnecessary shortcoming of the admirable English language. I understand that the Greek language contains separate words for the two entities. I shall use "daytime" for the sunlit period and "day" for the twenty-four-hour period.

Well, then, should the day start at sunrise or at sunset?

You might argue for the first, since in a primitive society that is when the workday begins. On the other hand, in that same society sunset is when the workday ends, and surely an ending means a new beginning.

Some groups made one decision and some the other.

The Egyptians, for instance, began the day at sunrise, while the Hebrews began it at sunset.

The latter state of affairs is reflected in the very first chapter of Genesis in which the days of creation are de scribed. In Genesis 1:5 it is written- "And the evening and the morning were the first day." Evening (that is, night) comes ahead of morning (that is, daytime) be cause the day starts at sunset.

This arrangement is maintained in Judaism to this day, and Jewish holidays still begin "the evening before' "

Christianity began as an offshoot of Judaism and remnants of this sunset beginning cling even now to some non Jewish holidays.

The expression Christmas Eve, if taken literally, is the evening of December 25, but as we all know it really means the evening of'Dccember 24-which it would natu rally mean if Christmas began "the evening before" as a Jewish holiday would. The same goes for New Year's Eve.

Another familiar example is All Hallows' Eve, the eve ning of the day before All Hallows' Day, which is given over to the commemoration of all the "hallows" (or "saints"). All Hallows' Day is on November 1, and All Hallows' Eve is therefore on the evening of October 31..

Need I tell you that AU Hallows' Eve is better known by its familiar contracted form of "Halloween."

As a matter of fact, though, neither.sunset nor sunrise is now the beginning of the day. The period from sunrise to sunrise is slightly more than 24 hours for half the year as the daytime periods grow shorter, and slightly less than 24 hours for the remaining half of the year as the daytime periods grow longer. This is also true for the period from sunset to sunset.

Sunrise and sunset change in opposite directions, either approaching each other or receding from each other, so that the middle of daytime (midday) and the middle of night (midnight) remain fixed at 24-hour intervals throughout the year. (Actually, there are minor deviations but these can be ignored.)

One can begin the day at midday and count on a steady 24-hour cycle, but then the working period is split between two different dates. Far better to start the day at midnight when all decent people are asleep; and that, in fact, is what we do.

Astronomers, who are among the indecent minority not in bed asleep at midnight, long insisted on starting their day at n-fidday so as not to break up a night's observation into two separate-dates. However, the spirit of conformity was not to be withstood, and in 1925, they accepted the in convenience of a beginning at midnight in order to get into step with the rest of the world.

All the units of time that are shorter than a day depend on the day and offer no problem. You start counting the hours from the beginning of the day; you start counting the minutes from the beginning of the hour; and so on.

Of course, when the start of the day changed its posi tion, that affected the counting of the hours. Originally, the daytime and the night were each divided into twelve hours, beginning at, respectively, sunrise and sunset. The hours changed length with the change in length of daytime and night so that in June (in the northern hemisphere) the daytime was made up of twelve long hours and the night of twelve short hours, while in December the situation was reversed.

This manner of counting the hours still survives in the Catholic Church as "canonical hours." Thus, " prime" ("one") is the term for 6 A.M. "Tierce" ("three") is 9 A.M., "sext" ("six") is 12 A.M., and "none" ("nine") is 3 P.M. Notice that "none" is located in the middle of the afternoon when the day is warmest. The warmest part of the day might well be felt to be the middle of the day, and the word'was somehow switched to the astronomic midday so that we call 12 A.M. "nOon.IY

This older method of counting the hours also plays a part in one of the parables of Jesus (Matt. 20:1-16), in which laborers are hired at various times of the day, up to and including "the eleventh hour." The eleventh hour referred to in the parable is one hour before sunset'when' the working day ends. For that reason, "the eleventh hour" has come to mean the last moment in which something can be done. 'ne force of the expression is lost on us, how ever, for we think of the eleventh hour as being either 11 A.M. or 11 P.m., and 11 A.M. is too early in the day to begin to feel panicky, while II P.m. is too late-we ought to be asleep by then.

The week originated in the Babylonian calendar where one day out of seven was devoted to rest. (The rationale was that it was an unlucky day.)

The Jews, captive in Babylon in the sixth century B.C., picked up the notion and established it on a religious basis, making it a day of happiness rather than of ill fortune. They explained its beginnings in Genesis 2:2 where, after the work of the six days of creation-"on the seventh day God ended his work wbich'he had made; and he rested on the seventh day."

To "those societies which accept the Bible as a book of special significance, the Jewish "sabbatb" (from the Hebrew word for "rest") is thus defined as the seventh, and last, day of the week. This day is the one marked Saturday on our calendars., and Sunday, therefore, is the first day of a new week. All our calendars arrange the days in seven colunins with Sunday first and Saturday seventh.

The early Christians began to attach special significance to the first day of the week. For one thing, it was the "Lord's day" since the Resurrection had taken place on a Sunday. Then, too, as time went on and Christians began to think of themselves as something more than a Jewish sect, it became important to them to have distinct rituals of their own. In Christian societies, therefore, Sunday, and not Saturday, became the day of rest. (Of course, in our modem effete times, Saturday and Sunday are both days of rest, and are lumped together as the "weekend," a period celebrated by automobile accidents.)

The fact that the work week begins on Monday causes a great many people to think of that as the first day of the week, and leads to the following children's puzzle (which I mention only because it trapped me neatly the first time I heard it).

You ask your victim to pronounce t-o, t-o-o, and t-w-o, one at a time, thinking deeply between questions. In each case he says (wondering what's up) "tooooo."

Then you say, "Now pronounce the second day of the week" and his face clears up, for he thinks he sees the trap. He is sure you are hoping he will say "toooosday" like a lowbrow. With exaggerated precision, therefore, he says "tyoosday."

At which you look gently puzzled and say, "Isn't that strange? I always pronounce it Monday."

The month, being tied to the Moon, began, in ancient times, at a fixed phase. In theory, any phase will do. The month can start at each full Moon, or each first quarter, and so on. Actually, the most logical Way is to begin each month with the new Moon-that is, on that evening when the first sliver of the growing crescent makes itself visible immediately after sunset. To any logical primitive, a new Moon is clearly being created at that time and the month. should start then.

Nowadays, however, the month is freed of the Moon and is tied to the year, which is in turn based on the Sun.

In our calendar, in ordinary years, the first month begins on the first day of the year, the second month on the 32nd day of the year, the third month on the 60th day of the year, the fourth month on the 91st day of the year, and so on-quite regardless of the phases of the Moon. (In a leap year, all the months from the third onward start a day late because of the existence of February 29.

But that brings us to the year. When does that begin and why?

Primitive agricultural societies must have been first aware of the year as a succession of seasons. Spring, summer, autumn, and winter were the morning, midday, evening and night of the year and, as in the case of the day, there seemed two equally qualified candidates for the post of beginning.

The beginning of the work year is the time of spring, when warmth returns to the earth and planting can begin.

Should that not also be the beginning of the year in general? On the other hand, autumn marks the end of the work year, with the harvest (it is to be devoutly hoped) safely in hand. With the work year ended, ought-not the new year begin?

With the development of astronomy, the beginning of the spring season was associated with the vernal equinox (see Chapter 4) which, on our calendar, falls on March 20, while the beginning of autumn is associated with the autumnal equinox which falls, half a year later, on September 23.

Some societies chose one equinox as the beginning and some the other. Among the Hebrews, both equinoxes came to be associated with a New Year's Day. One of these fell on the first day of the month of-Nisan (which comes at about the vernal equinox). In the middle of that month comes the feast of Passover, which is thus tied to the vernal equinox.

Since, according to the Gospels, Jesus' Crucifixion and Resurrection occurred during the Passover season (the Last Supper was a Passover seder), Good Friday and Easter are also tied to the vernal equinox (see Chap ter I).

The Hebrews also celebrated a New Year's Day on the first two days of Tishri (which falls at about the autumnal equinox), and this became the more important of the two occasions. It is celebrated by Jews today as "Rosh Hashonah" ("head of the year"), the familiarly known "Jewish New Year."

A much later example of. a New Year's Day in con nection with the autumnal equinox came in connection with the French Revolution. On September 22, 1792, the French monarchy was abolished and a republic pro 31 claimed The Revolutionary idealists felt that since a new epoch in human history had begun, a new calendar was needed. They made September 22 the New Year's Day and established a new list of months. The first month was Vend6miare, so that September 22 became Vend6 miare 1. . For thirteen years, Vend6miare I continued to be the official New Yeaes Day of the French Government, but the calendar never caught on outside France or,even among the people inside France. In 1806 Napoleon gave up the struggle and officially reinstated the old calendar.

There are two important solar events in addition to the equinoxes. After the vernal equinox, the noonday Sun con tinues to rise higher and higher until it reaches a maximum height on June 21, which is the summer solstice (see Chapter 4), and this day, in consequence, has the longest daytime period of the year.

The height of the noonday Sun declines thereafter until it reaches the position of the autumnal equinox. It then continues to decline farther and farther fill it reaches a minimum height on December 21, the winter solstice and the shortest daytime period of the year.

The summer solstice is not of much significance. "Mid summer Day" falls at about the summer solstice (die tradi tional English day is June 24). This is a time for gaiety and carefree joy, even folly. Shakespeare's A Midsummer Night's Dream is an example of a play devoted to the kind of not-to-be-taken-seriously fun of the season, and the phrase "midsummer madness" may have arisen similarly.

The winter solstice is a much more serious affair. The Sun is declining from day to day, and to a primitive so ciety, not sure of the invariability of astronomical laws, it might well appear that this time, the Sun will continue its decline and disappear forever so that spring will never come again and all life will die.

Therefore, as the Sun's decline slowed from day to day and came to a halt and began to turn on December 21, there must have been great relief and joy which, in the end, became ritualized into a great religious festival, marked by gaiety and licentiousness.

The best-known examples of this are the several days of holiday among the Romans at this season of the year. The holiday was in honor of Saturn (an ancient Italian god of agriculture) and was therefore called the "Satumalia." It was a time of feasting and of giving of presents; of good will to men, even to the point where slaves were given temporary freedom while their masters waited upon them.

There was also a lot of drinking at Satumalia parties.

In fact, the word "saturnalian" has come to mean dis solute, or characterized by unrestrained merriinent.

There is logic, then, in beginning the year at the winter solstice which marks, so to speak, the birth of a new Sun, as the first appearance of a crescent after sunset marks the birth of a new Moon. Something like this may have been in Julius Caesar's mind when he reorganized the Roman calendar and made it solar rather than lunar (see Chap ter I).

The Romans had, traditionally, begun their year on March 15 (the "Ides of March"), which was intended to fall upon the vernal equinox originally but which, thanks to the sloppy way in which the Romans maintained their calendar, eventually moved far out of synchronization with the equinox. Caesar adjusted matters and moved the beg ning of the year to January 1 instead, placing it nearly at the winter solstice.

This habit of beginning the year on or about the winter solstice did not become universal, however. In England (and the American colonies) March 25, intended to repre sent the vernal equinox, remainedthe official beginning of the year until 1752. It was only then that the January I beginning was adopted.

The beginning of a new Sun reflects itself in modem times in another way, too. In the days of the Roman Em pire, the rising power of Christianity found its most dan gerous competitor in Nfithraism, a cult that was Persian in origin and was devoted to sun worship. The ritual cen tered about the mythological character of NEthras, who represented the Sun, and whose birth was celebrated on December 25-about the time of the winter solstice. This was a good time for a holiday, anyway, for the Romans were used to celebrating the SatumaEa at that time of year.

Eventually, though, Christianity stole Mithraic thunder by establishing the birth of Jesus on December 25 (there is no biblical authority for this), so that the period of the winter solstice has come to mark the birth of both the Son and the Sun. There are some present-day moralists (of whom I am one) who find something unpleasantly remi niscent of the Roman Satumalia in the modem secular celebration of Christmas.

But where do the years begin? It is certainly convenient to number the years, but where do we start the numbers?

In ancient times, when the sense of history was not highly developed, it was sufficient to begin numbering the years with the accession of the local king or ruler. The number ing would begin over again with each new kin. Where a city has an annually chosen magistrate, the year might not be numbered at all, but merely identified by the name of the magistrate for that year. Athens named its years by its archons.

When the Bible dates things at all, it does it in this manner. For instance, in II Kings 16:1, it is written: "In the seventeenth year of Pekah the son of Remallah, Ahaz the son of Jotham king of Judah began to reign." (Pekah was the contemporary king of Israel.)

And in Luke 2:2, the time of the taxing, during which Jesus was born, is dated only as follows: "And this taxing was first made when Cyrenius was governor of Syria."

Unless you have accurate lists of kings and magistrates and know just how many years each was in power and how to relate the list of one region with that of another, you are in trouble, and it is for that reason that so many ancient dates are uncertain even (as I shall soon explain) a date as important as that of the birth of Jesus.

A much better system would be to pick some important date in the past (preferably one far enough in the past so that you don't have to deal with negative-numbered years before that time) and number the years in progres sion thereafter, without ever starting over.

The Greeks made use of the Olympian Games for that purpose. This was celebrated every four years so that a four-year cycle was an "Olympiad." The Olympiads were numbered progressively, and the year itself was the Ist, 2nd, 3rd or 4th year of a particular Olympiad.

This is needlessly complicated, however, and in the time following Alexander the Great something better was in troduced into the Greek world. The ancient East was being fought over by Alexander's generals, and one of them, Seleucus, defeated another at Gaza. By this victory Seleu cus was confirmed in his rule over a vast section of Asia.

He determined to number the years from that battle, which took place in the Ist year of the 117th Olympiad. That year became Year 1 of the "Seleucid Era," and later years continued in succession as 2, 3, 4, 5, and so on. Nothing more elaborate than that.

The Seleucid Era was of unusual importance because Se leucus and his descendants ruled over Judea, which there fore adopted the system. Even after the Jews broke free o If the Seleucids under the leadership of the Maccabees, they continued to use the Seleucid Era in dating their com mercial transactions over the length and breadth of the ancient world. Those commercial records can be tied in with various local year-dating systems, so that many of them could be accurately synchronized as a result.

The most important year-dating system of the ancient world, however, was that of the "Roman Era." This began with the year in which Rome was founded. According to tradition, this was the 4th Year of the 6th Olympiad, which came to be considered as I A.U.C. (The abbrevia tion "A.U.C." stands for "Anno Urbis Conditae"; that is, "The Year of the Founding of the City.")

Using the Roman Era, the Battle of Zama, in which Hannibal was defeated, was fought in 553 A.U.C., while Julius Caesar was assassinated in 710 A.U.C., and so on. This system gradually spread over the ancient world, as Rome waxed supreme, and lasted well into early medieval times.

The early Christians, anxious to show that biblical records antedated those of Greece and Rome, strove to begin counting at a date earlier than that of either the founding of Rome or the beginning of the Olympian Games. A Church historian, Eusebius of Caesarea, who lived about 1050 A.U.C., calculated that the Patriarch, Abraham, bad been born 1263 years before the founding of Rome. Therefore he adopted that year as his Year 1, so that 1050 A.u.c. became 2313, Era of Abraham.

Once the Bible was thoroughly established as the book of the western world, it was possible to carry matters to their logical extreme and date the years from the creation of the world. The medieval Jews calculated that the crea tion of the world had taken place 3007 years before the founding of Rome, while various Christian calculators chose years varying from 3251 to 4755 years before the founding of Rome. These are the various "Mundane Eras" ("Eras of the World"). The Jewish Mundane Era is used today in the Jewish calendar, so that in September 1964, the Jewish year 5725 began.

The Mundane Eras have one important factor in their favor. They start early enough so that there are very few, if any, dates in recorded history that have to be given negative numbers. This is, not true of the Roman Era, for instance. The founding of the Olympian Games, the Trojan War, the reign of David, the building of the Pyramids, all came before the foundin of Rome and have to be given negative year numbers.

The Romans wouldn't have cared, of course, for none of the ancients were very chronology conscious, but modem historians would. In fact, modem historians are even worse off than they would have been if the Roman Era had been retained.

About 1288 A.U.c., a Syrian monk named Dionysius Exiguus, working from biblical data and secular records, calculated that Jesus must have been born in 754 A.U.C.

This seemed a good time to use as a beginning for counting the years, and in the time of Charlemagne (two and a half centuries after Dionysius) this notion won out.

The year 754 A.U.c. became A.1). I (standing for Anno Domini, meaning "the year of the Lord"). By this new "Christian Era," the founding of Rome took place in 753 B.C. ("before Christ"). The first year of the first Olvmt)iad was in 776 B.C., the first year of the Seleucid Era was in 312 Bc., and so on.

This is the system used today, and means that all or ancient history from Sumer to Augustus must be dated in negative numbers, and we must forever remember that Caesar was assassinated in 44 B.C. and that the next year is number 43 and not 45.

Worse still, Dionysius was wrong in his calculations.

Matthew 2: 1 clearly states that "Jesus was born in Bethle hem of Judea in the days of Herod the king." This Herod is the so-called Herod the Great, who was born about 681 A.u.c., and was made king of Judea by Mark Antony in 714 A.u.c. He died (and this is known as certainly as any ancient date is known) in 750 A.U.c., and therefore Jesus could not have been born any later than 750 A.U.C.

But 750 A.U.c., according to the system of Dio'nysius Exiguus, is 4 B.C., and therefore you constantly find in lists of dates that Jesus was born in 4 B.C.; that is, four years before the birth of Jesus.

In fact, there is no reason to be sure that Jesus was born in the very year that Herod died. In Matthew 2:16, it is written that Herod, in an attempt to kill Jesus, ordered all male children of two years and under to be slain. This verse can be interpreted as indicating that Jesus may have been at least two years old while Herod was still alive, and might therefore have been born as early as 6 B.C. Indeed, some estimates have placed the birth of Jesus as early as 17 B.C.

Which forces me to admit sadly that although I lo begin at the beginning, I can't always be sure where beginning is.