A Calendar for Your Date — Part I

In our everyday world, a calendar is generally something that you hang on the wall, and by which you count off the days until some birthday, a vacation, or the next public holiday. A calendar is a much bigger concept than this, though, and it affects both genealogists and historians in ways that we don’t like to think about since they complicate our worldview.

So what is a calendar? A calendar is a mechanism by which dates are reckoned in a given culture. Historically, that meant that it allowed the passing of days to be recorded and so the return of the seasons or astronomical phenomena to be predicted.

There are six principal calendars in current use: Gregorian, Jewish, Islamic, Indian, Chinese, and Julian,[1] but a list of many historical calendars can be found at: List of Calendars. If we encounter a source with a date expressed according to one of these calendars then how should we represent it? Before I try and answer that, I want to give a small tour to illustrate how complex the subject is.

Calendars can be based on natural cycles, such as astronomical events, or contrived (man-made) cycles. The main astronomical systems are:[2]

Lunar. Calendars based on the counting of lunations: cycles of the phases of the moon. The average lunation is now known to be 29.530589 days, but historically it wasn’t known to that level of precision. Addition of an extra day, to get things back in step, might have been done on ad hoc basis rather than according to some rigid rule. Other problems — other than the natural fluctuations, and observing phase changes in bad weather — include the fact that the first instant of a new phase depends on both the latitude and longitude of the observer. The Islamic calendar is the only modern-day example.

Lunisolar. Calendars where the cycles of the moon and of the year (i.e. seasons) were combined and extra months occasionally added to keep them synchronised — sometimes relying on an arbitrary decision by a local priest rather than a formulaic approach. The Jewish, Chinese, Japanese, and Indian calendars are examples.

Solar. Calendars based entirely on the cycle of the sun, and abandoning those of the moon. Although our modern Gregorian calendar has months, these are not tied to the phases of the moon and so it is a solar calendar rather than a lunisolar one. Other examples include the Egyptian calendar, which had a fixed 365-day so-called “wandering” year, and the Julian calendar which had a fixed 365.25-day year.

The root of many problems with calendars based on natural cycles is that there is no fixed integral relationship between the periods of astronomical events such as the rotation of the earth about its axis (a day), the phases of the moon (a month), and the rotation of the earth about the sun (a year): their relationships are both fractional and continually varying. In fact, we cannot even say that the length of a day now is the same as it was at some point in prehistory because there was no common yardstick by which to directly compare them.[3] We can extrapolate our understanding of the motions within our solar system back to ancient times but they’re the predictable motions. If some asteroid had once passed close by the earth then it could have had a significant effect on the mean solar day. We’re currently aware of these fractional relationships by virtue of the leap-year where an extra day is inserted into our calendar every four years — except if the year is a multiple of 100, and it is not a multiple of 400. This process of adding a day (in general: intercalation) is simply trying to keep our notions of a day and a year in step.

Although several instances of contrived cycles have once existed, our most familiar modern-day example is the seven-day week.

The years themselves may be counted from the beginning of some reign or from some important or regular cultural event. Years counted according to the reign of some sovereign, monarch, or pope are termed regnal years. Even now, Acts of Parliament, in England, might be dated such as 3 Elizabeth II, meaning: third year of the reign of Elizabeth II. In ancient Greece, years were sometimes numbered according to the Olympiad: the four-yearly period between their successive games. The Japanese nengo system counts years according to a number of eras, originally determined by court officials but later determined by the accession of emperors (similar to the old Chinese dynasties). Our own modern year numbering is according to the Christian Era (AD/BC), also known as the Common Era (CE/BCE), although this has only a single epoch. Years in the French Republican calendar began with the Republican Era: the first year of the republic. Years may sometimes be named rather than numbered, as with Roman ones based on the name of a consul, or Greek ones based on the name of an archon. Knowledge of the associated epochs — the starting points for the counting — in some alternative calendar system is therefore a prerequisite for accurate conversion to it. This knowledge becomes less known as the importance of the epoch becomes more minor. In England, the records of manors held by the church sometimes used Episcopal or abbatial years. Even though the sequence of bishops or abbots is generally known, their exact dates may not be — especially in the case of minor abbots who did not sit in the House of Lords.

What the majority of the world uses today is known as the Gregorian calendar, named after Pope Gregory XIII who introduced it via a papal bull in 1582 as a replacement for the Julian calendar. The Julian calendar used a fixed year of 365.25 days, but the average tropical year is more like 365.24219 days, and that meant that events were drifting very slightly behind each year. A major problem was that Easter was defined by the First Council of Nicaea (AD 325) in relation to the spring equinox, and after nearly 13 centuries of the overly-long year its date had drifted backwards by about 10 days of where it used to be. As well as setting a new average calendar year of 365.2425 days, the Gregorian calendar removed 10 days in order to move Easter back to where it was before.

I don’t want to dwell too long on this Julian-to-Gregorian transition during this particular post (I’ll cover that another time) as there are many other calendar systems. I want to illustrate the complexities of those calendar systems, and explain how converting between them is not an exact science. If we allow our modern Gregorian calendar to be used in a proleptic fashion, where it can be used for dates prior to its invention, then we find that there is some uncertainty in translating dates from those other systems to our modern system.

The Julian calendar was introduced by Julius Caesar in 46 BC as a reform of the earlier Roman calendar, supposedly introduced when Rome was founded by Romulus in about 753 BC. The Roman calendar was a lunar calendar with 10 months (December being the 10^th month) and a year of 304 days. This was unworkable for farmers who needed to be more aware of the approaching seasons, and so Numa Pompilius (the second king of Rome), in about 713 BC, introduced two more months, thus making the year 354 days (12 x 29.5 days), although an extra day was added to make it 355 for superstitious reasons. This still drifted with respect to the solar year and so several schemes were devised to try and improve it using intercalary days or months. However, the decision of when and how-much were usually in the hands of the priests who shamelessly misused that power — when they hadn’t neglected the actual need — for political reasons (e.g. changing the term of someone’s office) or financial advantage (e.g. taxes, rents). When the Julian calendar was introduced, there were so many corrections to put things back in order that 46 BC was a year of some 445 days, often referred to as “the year of confusion”. In effect, there are many calendar variations here, and some rather irregular intercalations.[4]

The Revised Julian calendar was a variation conceived in 1923 that allowed the years of the Julian calendar (still used by the Eastern Orthodox Church) and Gregorian calendars to remain in step — at least until the year 2799.

Although often overlooked, the extra day in leap years of the Gregorian calendar was originally achieved by repeating the 24^th February; a practice inherited from the Julian calendar. It wasn’t until 1662 that it was achieved by adding an extra day at the end of February. Today, a residual repercussion of this is a difference in the date of the feast of St. Matthias during leap years as celebrated by the Catholic and Anglican churches.[5] Earlier still, different Christian churches in Romanised Britain celebrated Easter one day apart.[6] In effect, knowing the name of a celebration or festival doesn’t uniquely determine its date.

The Islamic calendar is the only surviving lunar calendar. It consists of 12 months of alternating 29 and 30 days over a 30-year cycle, except in embolismic years where an intercalary day is added at the end of the 12^th month. There are 11 such intercalations and so each 30-year cycle has 10631 days (30 x 12 x 29.5 + 11), and this keeps the month in synchronisation with the moon. There are some variations of the actual years in which the intercalation occurs but it is essentially a rule-based calendar. It is sometimes called the Tabular Islamic calendar in order to distinguish it from the “popular” Islamic calendar where the actual start of each month is determined by a religious authority based on the first visibility of the crescent lunulae of the new moons. This empirical approach is obviously problematic as the appearance depends upon the weather and geographical coordinates, and the date can be one or two days different from the calculated one. It can therefore vary from one part of Islam to another.[7]

India’s calendars are particularly troublesome as they are “…intricate, complex, and subject to numerous local variations”.[8] Most are lunisolar but there are solar calendars too. When India became independent, in 1947, their first Prime Minister, Jawaharlal Nehru, set about a number of reforms, and one of these involved the Indian Calendar Reform Committee, appointed in 1952. They found that there were over 30 well-developed calendars in use across India, and they set about creating a unified Indian national calendar, which was adopted on 22 Mar 1957. However, India’s diverse population meant that the Gregorian calendar was still used (by Christians and for administration), and also the Islamic calendar. Indian and Gregorian dates are therefore presented side-by-side by The Gazette of India, in news broadcasts by All India Radio, and in calendars and communications issued by the Government of India.

In the older Indian calendars, the variations of the lunisolar ones included different month names, the date of the start of the year, the phase of the moon on which the year or month started, intercalation rules, and the era from which years were counted, thus making any attempt at general conversion to Gregorian dates “futile”.[9] However, the solar calendars, used in parts of Bengal and Madras, “were susceptible to almost infinite variations”, thus making it very difficult to convert an Indian date to a Gregorian one without specific knowledge of the calendar and locality.[10]

A similar story of innumerable variations applies to the Chinese calendars.

What I wanted to emphasise in this first post is that conversion from these other calendars to our Gregorian one is not simply a matter of looking at the written form and then doing some arithmetic. Even when the calendar system was rule-based, rather than dependent upon observation or ad hoc decisions, the conversion may need information about the actual calendar variant being used, their location, their religion, etc.

If an historian recorded a length in cubits then a very similar situation would arise since there were different cubit definitions used in different places. A write-up may give an indication of what that length might have been in feet (or metres) but the converted value would need substantiating, and it wouldn’t be a direct replacement for the original information.

To genealogists, a more familiar case might be how we handle dates and ages in our sources. Even if we encounter a date in our own calendar then it may be incomplete, or it may be secondary information. Although many genealogists treat them as “facts”, there’s no such thing in principle. With ages then we should be seeing the issue more clearly: we certainly don’t perform a simple subtraction of the age from the date of recording, and then use that date as a “fact”. Someone may have lied about their age, or it may have been age-next-birthday rather than age-last-birthday (as in early Canadian censuses), or it may have been rounded down (as in 1841 census of England and Wales). The essential point is that the calculated date is not information that was in the consulted source; it is derived from it, and it may need more information in order to make that derivation. Any calendar conversion is also a calculation, and similarly different from source information.

In Part II of this post, I want to look at the representation of dates from other calendars, and why a general scheme should be important to us.

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[1] “Introduction to Calendars”, USNO (http://aa.usno.navy.mil/faq/docs/calendars.php : accessed 10 Jul 2015), first paragraph.

[2] E. G. Richards, Mapping Time: The Calendar and its History (1998; reprint, Oxford University Press, 2005), pp. 92–97.

[3] An examination of fossil records has shown that a year once consisted of nearly 400 daily cycles, but finding the length of one such cycle is harder to determine. Observations have shown that the earth’s rotation is slowing down, and calculations suggest that it was once substantially faster — some reports as low as 16 hours per day. That would result in a greater centrifugal force acting against gravity, and things would probably have felt lighter millions of years ago.

[4] David Ewing Duncan, The Calendar (London: Fourth Estate Ltd, 1998), pp.40–43.

[5] Richards, p.101.

[6] Duncan, pp.104–5.

[7] Richards, p.93, p.234.

[8] Richards, p.174.

[9] Richards, p.182.

[10] Richards, p.177.

Old Dogs, New Tricks

As well as taking a brief look at the relationship between evidence, inference, and conjecture, I also want to explain why it’s so important to remember the level to which each of your statements is substantiated. If we accidentally promote some statement beyond that level then we will be distorting our knowledge, and hence our representation of history.

This is not saying that we can only make “proven” statements, or even just substantiated ones; we’re entitled to make whatever statements we see fit in our research, including conjecture, rumour, through hypothesis and theory, to some conclusion that we have a degree of confidence in. This range is necessary since it will be impossible to know everything, or to prove anything at all in the strict sense (see Proof of the Pudding), but we still want answers. What we should not do is to pretend, to ourselves or to others, that something is more than what it is.

Having come to genealogy from a scientific background, I have often claimed it as a paragon of virtue when it comes to evidence-based analysis and understanding of the universe. For instance, when someone recently posted a quote from one of the greatest physicists of the 20^th Century, Richard Feynman (“I’d rather have questions that can’t be answered than answers that can’t be questioned” — no room for dogma there, old or new), I just had to add a comment about his exceptional approach to academic integrity. I still research topics in physics, but what I didn’t anticipate is subconsciously applying some of my new critical genealogical thinking when subject-hopping. It does seem that old dogs can pick up new tricks!

Figure 1 – Oh no, he's done it again! New ball, please!

Genealogy

Evidence, more than any other genealogical concept — including proof — is hard for most of us to fully grasp. Evidence is often defined as information that is used to support or refute some claim. It therefore involves some interpretation by a researcher, and their interpretation may not be the same as that of another researcher. In other words, it’s a relative concept: relative to both the claim and the researcher. Without the specific claim then information cannot be deemed evidence of anything, and without the researcher then the raw information cannot be interpreted to derive that evidence.

I admit to struggling with the concept myself, and I think part of the reason is the loose way that we use such terms in everyday speech. One of my ways of working, which I call Source Mining, involves reading the raw information in a source, such as a newspaper, and tagging items that I believe will be relevant to a particular piece of research. I’m effectively collecting references that may be significant, to a lesser or greater extent, to my overall goal: that of writing about the history of some person, family, industry, or place. Those items aren’t evidence because I have not made any specific claims. When I’ve consulted several sources then I begin looking for correlations between them: items that support or contradict each other, as well as assembling things into a timeline. But they’re still not evidence! It’s only when I make a specific claim or statement, such as ‘A was the child of B and C’ or ‘A moved from X to Y in 1887 because he changed jobs’, that I need to substantiate it. I then link my statement to those selected items of information, or to my written analysis if those informational items don’t yield direct and non-conflicting evidence by themselves.

So, it’s not necessarily the case that we set out with a specific research question. Evidence is related to the claim or statement rather than to the way it was derived, or even to the reason that it was sought. The above methodology makes the connections in the bottom-up direction (meaning building upwards from the raw information) rather than in a top-down direction where the research is framed by a specific question. My overall goal did not constitute a question and so the information I’d assimilated did not constitute evidence of anything related to that goal.

Let me take a simple example from Who Was Simeon Webber? I had found that the marriage of Simon Webber — the railway labourer — to Elizabeth Samson occurred over 18 years after the birth of their first child, Mary Ann Webber (actually 18 years 106 days, according to my Date Subtraction Tool). The associated birth and marriage certificates provided direct evidence of those events, but did not shed any light on why there was such a huge gap. At that point, any suggested reason would have been pure conjecture or speculation since there was no information to point the way. Such speculation isn’t necessarily idle since it may direct future research efforts in an attempt to support or refute the possibility.

At a later stage, I found that the family had emigrated from England to the US, and I had several sources confirming their residency in Illinois. As well as those sources providing direct evidence of their residency and naturalization, they provided indirect evidence[1] for a reasonable explanation of the late marriage: it must have been easier to emigrate as a family if there was paperwork to back it up — especially if US immigration back then was anything like it is now. The difference was that I then had some extra information that I could interpret in order to make some inferences.

But I couldn’t say that I knew this; it would have been a theory or a hypothesis (which is a sort of prototype theory)[2] depending on how much I knew of US immigration during that time period. That evidence merely supported my hypothesis, but it also supported alternatives too. As it stood, I was confident that the trigger for the marriage was the major event of emigration, but not of the specific reason for it. Was it the potential difficulties in being admitted as a family with no marriage (I have read about polygamous marriages and under-age wives being issues during 19^th Century US immigration), or was it to do with property rights, or to custody of the children should something happen during the journey? My evidence only really supported the claim that emigration was the trigger for the marriage, but I would need more information before I could claim anything more specific than that. Of course, none of the information that I had shed any light on why they didn’t marry in the first place — that’s a whole different question.

You may have wondered why academic historians don’t put such emphasis on the finer details of their research, including the “proof” of event dates, relationships, etc. They might argue — erroneously in my opinion — that the small-scale information doesn’t matter that much when they’re researching large-scale history, relevant on a national or global level, and that genealogy, being a form of micro-history, is more dependent upon them. Even if we accept such an argument, how many historical articles have you read that distinguish individual claims and statements according to how well they are substantiated? If they don’t differentiate between something supported directly and something they’ve inferred, including to what level of confidence, then another historian may regurgitate it as “fact”. Biographers are notoriously guilty of similar faults, and yet their goal is much more of a micro-history so they have no excuse.

Science

There are a number of sciences that relate to the past, such as archaeology, Egyptology, palaeontology, and geology. They can all be forgiven for having to make some inferences on the best available information at the time, but they rarely distinguish between what has been found or measured, and what is the interpretation of it. Worse still, especially on the TV, that interpretation is generally presented as though it were fact, and any professional opinion that differed from the mainstream view, or from some acknowledged expert, may be risking that person’s career. This can be a sinister side of science, and I had believed that physics was beyond that.

I’m currently taking another look at physics because it’s just as guilty in some ways. There are many things that are depicted as fact when they’re merely theory, and — worse still — some blatant misrepresentation of what mathematical physics is telling us. Believe me when I tell you that this is worse than suggesting some genealogical information tells us something when there’s obviously some interpretation required. You see, mathematics does not describe cause-and-effect; it describes a continuous relationship between certain variables. The equation that describes the path of a cannonball does not say that it was ejected from a cannon to finish on the ground, or vice versa; it merely describes the total path.

Let me select a popular subject as an example: the Big Bang. The public are led to believe that there was a massive primordial explosion from which the universe was created. Well, that’s wrong on just about every count. The event would not have been big; it would have been infinitesimally small. There would have been no bang because there was no space, no air, and no one to hear it. There wasn’t even an explosion because that implies material expanding into pre-existing space, whereas space and time supposedly began at this event. In fact, the whole event is inferred from the extrapolation of certain stellar spectral measurements that imply all stars are travelling away from each other. A similar story can be seen in topics such as quantum theory, relativity, etc. I have always considered myself to be an extreme sceptic but I intend to reapply my critical thinking in these areas very soon.

Conclusion

So what can we learn from this? Critical thinking is good; think like a detective. We can’t always expect solid evidence and so we’ll have statements that vary widely in the level to which they’re substantiated — just make sure you remember those levels by documenting any evidence, where it came from, and how it relates to your statements. A guess is fine as long as you remember that it’s a guess, and don’t promote it without more evidence. Understand what you’re doing, and why, during your research, as opposed to blindly following a prescription. If you think you’re being hassled by so-called genealogy police, just remember that people who advocate a prescription probably need a prescription.

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[1] Elizabeth Shown Mills, “QuickLesson 13: Classes of Evidence―Direct, Indirect & Negative”, Evidence Explained: Historical Analysis, Citation & Source Usage (https://www.evidenceexplained.com/content/quicklesson-13-classes-evidence%E2%80%94direct-indirect-negative : accessed 15 Jun 2015).

[2] Elizabeth Shown Mills, “QuickLesson 16: Speculation, Hypothesis, Interpretation & Proof”, Evidence Explained: Historical Analysis, Citation & Source Usage (https://www.evidenceexplained.com/content/quicklesson-16-speculation-hypothesis-interpretation-proof : accessed 15 Jun 2015).

Light-Bulb Moments

Listening to the continuing discussions within FHISO, I have to wonder whether something is missing; something that's fundamentally necessary for the production of a data standard for genealogy. Let me start with a question: how many programmers does it take to change a light bulb?

There are many instances of this, and similar, jokes on the Internet. The most common answer is:

"None. That's a hardware problem."

A less common one, aimed specifically at Windows programmers, is:

"472. One to write WinGetLightBulbHandle, one to write WinQueryStatusLightBulb, one to write WinGetLightSwitchHandle, ... etc ..."

Alternatively:

"None. Darkness is a software 'feature'."

What these jokes demonstrate is the popular notion of the programmer as someone who lives in a virtual reality, and who is not fully connected to the real world. Coming from this background myself, I have to admit that there are rather too many real instances of the stereotype for me to be entirely comfortable with the jokes. But is this a fair criticism of programmers, software developers, and other software people, working in the genealogy field?

If I extrapolated that notion to a real bulb-changing scenario then I might imagine the programmer taking careful note of the bulb fitting. Is it a bayonet or screw fitting? If it’s a screw fitting then what size is it? What shape bulb is required: standard, golf-ball, pygmy, or other? Does the replacement conform to national standards? Should they use a low-energy one as they’re the way to go — allegedly?

The problem is that a consideration of the change as an isolated exercise — no matter how deep the attention to detail — will miss the fact that the result has to perform a particular function. Without an examination of the functional requirements then the appropriate power rating (wattage) and bulb colour may be wrongly selected.

OK, enough of the analogies before I get lynched. My point is that the FHISO mailing lists are currently dominated by programmers and other people with a background in software development. There are some particularly brave non-programmers on those lists, and their astuteness and functional focus are both very noticeable. Dialogue between the two groups has helped to rescue the concept of genealogy from the mire of BMD data and family trees, but software thinking continues to retreat back into that safe world; a place where the computer needs to understand everything, and anything written in a national language — including research notes, proof arguments, and conclusions, if not general biographical narrative — is too flexible and ill-defined.

There’s a subtle issue here, concerning the programmer’s attitude to genealogy, that isn’t seen in most other industry sectors. Software may be applied to a huge range of activities, including: banking and financial services, business, healthcare, manufacturing, accounting, aerospace and defence, government, engineering, and education — to name but a few. It would be extremely rare to find programmers who knew these subjects to a level  that required no functional requirements from anyone else, and yet that is frequently what happens in the genealogical sector, so why is that?

Interestingly, international and cultural differences are topics that both groups can make gross assumptions over. Unless they have specifically studied such differences, or researched in alternative locales, then they can both be guilty of retreating into their own native norms and cultural traditions; they both need functional inputs from authoritative sources.

Part of the genealogical difference may arise from a chicken-and-egg case of “what you see is what you get”. Early software products were quite naïve in their understanding of genealogy, and that image has been perpetuated by the advertising and online tools of the major genealogical companies. It’s hard to break ranks when everything you see appears to follow the same paradigm.

Another part of the difference will certainly be due to the fact that those programmers supposedly indulge in some form of genealogy, and so as consumers they’re effectively writing their own specifications. This is a very important factor since it’s hard to assess the type of genealogy they indulge in, or to what depth of knowledge they aspire.

This should not be taken as a suggestion that they’re bad genealogists, or that they do not indulge at all, but simply that their work is rarely evident. This is actually a fault of many genealogists, from the amateur through to the professional; very few of us publish our genealogical works beyond mere trees, and some don’t even do that. Is that for reasons of confidence, capabilities, copyright, or something else beginning with ‘c’? Unfortunately, in the absence of such public material, how can we possibly know that we’re trying to solve the same problems, or aim for the same goal?

There is a core group of genealogists who publish written works on their Web site or their blog, and I take my hat off to them. They capture much more than a mere tree would, and offer readable material for friends, family, and colleagues to access. Professionals and academics may publish articles in genealogical journals, where they would be read by their peers, but far less so online. It was suggested to me recently that their drive to produce reliable and well-documented works may be construed as elitism, and so they would rather avoid that level of criticism. I made a conscious decision to publish written genealogical works on my own blog — with some initial trepidation as I was neither writer nor historian — primarily to show the type of genealogy that I do, and to put some context around my software views and requirements. Although I include citations in those works, I do admit to some embarrassment over them. There are definitely folks who see citations as some sort of elitist competition, rather than a matter of research integrity, and so I find myself trying to “nibble off the edges”, and so reduce their volume — probably as a journal editor might.

This general situation is sad for a couple of reasons. Firstly, genealogy needs more online works to guide and inspire others. There is so much value that can be added through writing, not just in capturing recollections but also in explaining your journey through time and sources to capture the lives of your antecedents. Secondly, in the context of FHISO, working on a standard for representing our data will be an impossible task if we cannot determine the range of our collective goals. We all have different notions of what constitutes genealogy, and although many will have similar notions, some will have quite dissimilar ones. Writing a specification for your own personal style, approach, and goals is a dangerous pitfall.

Maybe we’ll be in the darkness for some time to come, unless someone manages to change that broken bulb.