There was a time when the idea of Santa Claus, wizards and aliens with one eye, all seemed perfectly plausible. But the idea that a number had some special nature that other numbers did not, never made any sense. Indeed, even though at one point even the idea that the whole universe was just a fantastic fabrication of the mind was considered worthy for evaluating; the idea that the number 13 was any more or less lucky than any other, seemed absurd.

Superstitions arise from religious beliefs in actual demons or evil forces that you can interact with, or from vague feelings without consideration from a rational perspective, as in a mad person’s delusions, and indeed all superstition is technically speaking a mental illness as it affects us adversely and is out of our control. It can also arise out of the belief certain things really are scientifically unluckier than other things. After all walking under a ladder might lead to the hospital if a contractor drops a hammer on your head!

The idea that an arbitrary integer like 13 is any more or less lucky than another requires some thought. Firstly we must assess things from the most rational perspective possible, the mathematical. 13 is the thirteenth number. It is three more than ten. Ten is a nice round decimal number that we feel nice and at home with. But it was not too long ago that we were using sixpences and farthings.

A dozen was, at the time of sixpences, a common amount for counting lots of items in. Buying in bulk we would buy a dozen or half dozen eggs. The number is rounded and can be stored in a neat container. But just because 13 is close in proximity to a nice round figure doesn’t indicate anything. Otherwise 9 and 11 would be very unlucky or lucky. Indeed, considering superstition and religion, 6 is the Devil’s number, so 6,12,18 etc., ought to be unlucky numbers. 6 times 6 is 36. So thus according to that myth, 36 is the most unlucky or evil number.

But before you go stabbing your voodoo doll of your hated boss, who refused you that raise 36 times, it may be wise to consider that there are many superstitions surrounding numbers. 21 is the age when a man traditionally gained acceptance into society, at least in England in the 1850s. But in the Empire it was 14, and who knows how many customs relating to ages in years there were in the other societies of the modern and ancient world.

Numbers can be represented in various ways. Shapes, defined by numbers, whether 2d or solid, have been like numbers qualities of wickedness or benevolence, usually because of some absurd and subjective idea they give us, such as rounded shapes being ‘kinder’, and sharp-edged triangular shapes being ‘harsher’. Thus numbers that end in two are more likely to be kindly and wholesome, whereas odd numbers like 3,6,9 etc., would assume demonic or at least criminal forms if anthropomorphised.

13 seems like Bart Simpson. A well-rounded boy in so many ways, but with that all important spicy dash of rebellion and skateboarding. Emily Strange, who is very beautiful in a bewitching and madness-inducing sort of way, is 13 years old. Strange to note that cats have 9 lives though. There are twelve months in a year, but years are based on the Sun’s transit across our sky, which is a rounded circuit if not perfectly circular as was formerly thought.

Numbers, however, in reality are just what they pretend to be. Numbers. They mean an amount, a relative amount or an absolute amount, but in either case no array of integers will ever attack you. However a dagger 13 centimetres long and 13 millimetres wide might inflict great harm to anyone. Then again so would a dagger of 15 centimetres in length!