> September 1752 had 19 days: 1, 2, 14, 15, ..., 29, 30.
That's only in the British Empire. Other countries moved to the Gregorian Calendar at different times. It began being adopted on 15 October 1582 (the day after 4 October 1582) in some Roman Catholic countries (Spain, Portugal, Italy, Poland). Russia didn't switch until 1918.
So, you could also have:
N+8. There is only one calendar system in use at one time.
And the list hasn't actually covered the Gregorian calendar at all, since many people may not know the actual leap year rule.
N+9. There is a leap year every year divisible by 4.
The actual rule is that there is a leap year every year divisible by 4, except those divisible by 100, with a further exception to that exception for years divisible by 400, (so there is a leap year on such years). The year 2000 is one such year divisible by 400, so we have not yet passed a year divisible by 4 which is not a leap year since the invention of computers.
It was a bug in Lotus 1-2-3 that was intentionally implemented into Excel, so technically it was a backwards-compatibility "feature". And some items from the original list aren't exactly "truths" as much as implementations or configurations, e.g.
> 19. The system clock will never be set to a time that is in the distant past or the far future.
That's only in the British Empire. Other countries moved to the Gregorian Calendar at different times. It began being adopted on 15 October 1582 (the day after 4 October 1582) in some Roman Catholic countries (Spain, Portugal, Italy, Poland). Russia didn't switch until 1918.
So, you could also have:
N+8. There is only one calendar system in use at one time.
And the list hasn't actually covered the Gregorian calendar at all, since many people may not know the actual leap year rule.
N+9. There is a leap year every year divisible by 4.
The actual rule is that there is a leap year every year divisible by 4, except those divisible by 100, with a further exception to that exception for years divisible by 400, (so there is a leap year on such years). The year 2000 is one such year divisible by 400, so we have not yet passed a year divisible by 4 which is not a leap year since the invention of computers.