Quite by accident, just the other day I found myself embroiled in a controversy on Twitter of my own making. I made an offhand mention that the decade would be ending in a few short days. That seemed obvious enough to me, but apparently not so to many others. What ensued was something of a firestorm of people, many of whom disagreed with me. However, I maintain that I was right all along. Here’s the scoop.

My claim is that December 31, 2009 — today, as this is posted — is not just the last day of the year, but the last day of a decade. Now, I don’t mean that in the trivial sense that any moment is the last moment of the past ten year period — you can always talk about the last ten years that end at any time.

I meant, and still mean, specifically the first decade of the 2000s. That does in deed and in fact end today.

What people were arguing over were things like centuries and millennia, and how there was no year 0, and therefore the last day of the decade is actually December 31, 2010. But that’s not relevant because we don’t measure decades the same way we do centuries.

Certainly, the last day of the 20th century was December 31, 2000. In that case, there was no year 0, so the first year of the 1st century ended on December 31, 1 A.D. Doing the math, it’s easy to see that 1999 more years needed to elapse to end the 20th century, and so its demise was on that last calendar day of 2000. January 1, 2001 marked the first day of the 21st century.

But we don’t reckon decades like that. We refer to them by the tens place in the year’s numerals: the 70s, the 80s, the 90s. And since we do, clearly, today is the last day of the decade we will call the aughts or zeroes or whatever.

Actually, looking at this now, it seems to me that centuries are more formal, with an actual method of naming them, whereas decades are more of a nickname, a handy handle to use when referring to a time period.

Also, you wouldn’t say that 1990 was part of the 80s, would you? I think it’s clear that December 31, 1989 was the last day of the 80s, just as December 31, 2009 is the last day of whatever term we’ll wind up using to refer to the first 10 years of the 2000s.

Confusing this a bit is that we might refer to something happening in the 1900s versus saying it happened in the 20th century. Those terms are synonymous, barring the year of 1900, which was in the 19th century, and 2000, which was in the 20th century but not in the 1900s.

If we did reckon decades the same way as centuries then a point would be made that the decade ends in 2010. But we don’t, and in this case there truly is a year 0: the year 2000. So once again, the first decade of the 2000s ends today.

A couple of people pointed out that this means the first decade in our calendar only had 9 years: AD 1 – 9. I suppose that’s true, and so it’s not really a decade then in the strict definition of the word. But since we’re not using a rigorous naming convention, and references to decades are more like nicknames. Plus, who talks about the first ten years of our calendar that way anyway?

Confusing this even more was the case someone made that when you are 30, you no longer say you are in your 20s (unless you’re lying). But all during that last year, when you say you are 29, you are actually living your 30th year on Earth. After all, when we say a baby is 1, really they have already been around 12 months. We change the number after the fact, so when you turn 30 you’ve already lived out your 30th year. The whole time you are 29, you’re plowing through your 30th year.

Perhaps it would lessen the issue if, when asked how old you are on your birthday, instead of saying "I am 30," you say "I have just completed my 30th year." I suspect that won’t catch on, however.

Still, be all that as it may, when you are 29 you are still in your 20s, and when you turn 30 you ain’t.

The lessons here are many fold. One is that, and pardon my repetition, the first decade of the 2000s ends today. A second is that people are still terribly confused about how to delineate centuries. A third is that this can be generalized to people being confused on how we delineate time.

Fourth is that this is all arbitrary and a bit silly. But we do make rules, and sometimes those rules have to make sense, and sometimes it’s fun to talk about them even when it means some people disagree.

And fifth? People shouldn’t argue with me on Twitter. At least not until the next decade starts.

And if I may indulge myself, one final thing:

Happy new year!

And happy new decade. May the 10s and teens treat us all better — and may we make them better — than the aughts.

ABC News reports on an unusual and tragic case of a heart attack triggered by blasting music. A British teenager died shortly after complaining of loud music at a London nightclub, according to reports. Details are sketchy but U.S. doctors suspect a genetic condition may be to blame.

From ABC News:

“Any time someone in a setting of excitement has a sudden cardiac arrest, especially at a young age with a seemingly normal heart, you have to consider [an inherited condition] such as long QT,” said Dr. Richard Page, chair of medicine at the University of Wisconsin School of Medicine and Public Health and president of the Heart Rhythm Society. “One of the genetic variants is especially predisposed to having an arrhythmia when exposed to loud sound.”

Long QT, an inherited affliction, is named for the points Q and T on a heart monitor. Longer-than-usual intervals between these points is one
major marker of this syndrome. People with QT can go into cardiac arrest when exposed to loud sounds such as alarms, music or sirens. Although it’s a rare disorder, it’s also deadly if left untreated. Fortunately, EKGs and genetic tests can detect most cases and pacemakers have been proven to help considerably.

As for the sad case of the British teenager, the world may never know if loud music killed him. Only an autopsy can confirm this and his family
is keeping mum for now.

Related Content:
Discoblog: Health Hazard Alert: Head-Banging May Hurt Your Brain
80beats: Seriously: Frank Sinatra Songs Restored Eyesight to Stroke Patients
80beats: Clubbers More Likely to Give Cigarettes If You Ask Their Right Ears

Image: flickr / Kaloozer

This week, a eight-year double-blind study of the nutritional supplement ginkgo biloba finally reached the pages of the Journal of the American Medical Association. Many health food stores sell ginkgo supplements to people who are hoping to improve their wits and memory, and particularly to elderly people worried about cognitive decline and dementia. But the conclusion by lead researcher Steven DeKosky? Save your money.

In the GEM [Ginkgo Evaluation of Memory] study, participants aged 72-96 years with little or no cognitive impairment were recruited from four communities in the eastern United States and received either a twice-daily dose of 120-milligrams of extract of G biloba or an identical-looking placebo [AFP]. For the more than 3,000 study participants, researchers found no difference in age-related cognitive decline—including the incidence of dementia or Alzheimer’s—between ginkgo takers and placebo takers.

What about younger people taking ginkgo? The findings don’t necessarily apply to acute use of the extract — or to younger patients who are attempting to prevent disease many years in the future. Yet DeKosky noted that “there’s nothing about antioxidants that would make you think they’d help in the short-term” [ABC News].

For more, check out this post by Phil Plait at Bad Astronomy.

Related Content:
80beats: Lack of ZZZZs Linked to Alzheimer’s in Mice
80beats: New Theory of Alzheimer’s: Brain’s Memory Center is “Overworked”
80beats: Herbal Remedy Doesn’t Help Kids With Attention Deficit Disorder
DISCOVER: Alternative Medicine Man

Image: Wikimedia Commons / darkone