One of my favourite topics of rants in the real world is how gullible the internet is making us all.
Until fairly recently, we'd not have believed what people say to us unless they had some kind of reputation for telling the truth and/or knowing a lot about the subject upon which they are expounding.
Yet nowadays millions of people repeat "stuff" as if it was a fact with all the authority of a national academy of sciences, just because they saw it online.
I've been especially amazed over the last few days by a statement that keeps coming into my email inbox and has taken Twitter by storm:
The basic form is:
This month has five Fridays, five Saturdays, and five Sundays, and this only happens once every 823 years!
Well yes, October 2010 does indeed have five "long weekends". But is this really such a rare occurrence?
Think about it for a moment:
In order for a month to have five Fridays, Saturdays and Sundays, it must be a 31-day month (January, March, May, July, August, October, December) and the first day of that month must be a Friday (so that it's Friday, Saturday and Sunday which are repeated rather than any other contiguous 3 days).
A 365-day year is 52 weeks and one day. As a result, successive years start on the day of the week after the year before (eg 1st October 2009 was on a Thursday, 1st October 2010 was a Friday and 1st October 2011 will be a Saturday). So in principle every seven years should be the same.
But we get leap years every 4 years (minus a few corrections) so the changes aren't all that regular. But on average every eight years we get the same days of the month on the same days of the week - nowhere CLOSE to 823 years!
Just so that you don't have to take my word for it, check any calendar (there are loads online), for how many Fridays, Saturdays and Sundays there were in October 2004 and 2010, and will be in 2021.
The basic numbers of days and months in a year (a 52 week year equals 13 4-week "months" rather 12 variable-length months) mean that, on average, every EIGHTH MONTH has five Fridays, Saturdays and Sundays which makes the event in general actually quite common. May 2009 and January 2010 were recent examples, and the next one after October 2010 is July 2011. Ask anyone who is paid every fourth Friday rather than calendar monthly for their experience.
Furthermore, the WHOLE of the 2010 calendar is exactly the same as 1999.
What has happened to the world and everyone's faculty for critical thinking if they accept this idiotic 823 years statement without a moment's hesitation?
Is it any wonder that the creationist/young earth movement is getting more and more adherents if people accept what's said to them without thinking about it?
I'm especially concerned by a variation on this meme which adds that years with a date which can written 10/10/10 only happen every 823 years.
How the FUCK can a decimal year (i.e. a year ending in 10) happen with a frequency other than 10 years apart? 10/10/10 happens every 100 years, the next time being in 2110.
I can't be bothered to do the exact calculation, but the combination of 10/10/10 AND the five long weekends in October happens roughly every 400 years.
In any event, it's NOT going to be a frequency ending on 3!
823 years from now is going to be 10/10/2833
Surely nobody even has to THINK about this for more than a millisecond? Surely it is self-fucking-evident?
Why the hell do people think that retweeting/re-emailing this kind of complete BOLLOCKS makes them appear to be anything other than illiterate, innumerate and incapable of rational thought?
Comments welcome, because I am really curious why being given a network connection seems to make otherwise intelligent people into gibbering baboons?