Azrael, the angel of death Evelyn De Morgan (18551919) 
For an educated
classical Greek, the number 8 represented death.
Why? Let’s see what this funeral assignment was based on.
 Multiply by 8 the first 8 natural numbers.
 Add the digits for each result.
 If the total obtained has more than one digit,
we add those digits again.
Multiply

Add digits

2nd addition

1×8=8

8

8

2×8=16

1+6=7

7

3×8=24

2+4=6

6

4×8=32

3+2=5

5

5×8=40

4+0=4

4

6×8=48

4+8=12

1+2=3

7×8=56

5+6=11

1+1=2

8×8=64

6+4=10

1+0=1

Observe that we obtain the sequence 8,7,6,5,4,3,2,1. For the Greeks,
this succession starts at 8 and descends to die
at 1. That is why number 8 represented death.
Remember that the Greeks did not have a zero, so the death
of the succession of decreasing numbers took place at value 1.
Zero is a very special number, which has in principle two different
meanings, although at bottom they are related:
 Number zero, the limit of many decreasing and increasing successions,
located between the succession of positive numbers (1,2,3...) and the
succession of negative numbers (1, 2, 3...). This should be the real symbol of death.
 Positional zero, which in our numerical notation of base 10
tells us that a number is missing (i.e. there is a jump in the power
series of 10). Thus, 107 means that to obtain this value we must add one
hundred and seven units, skipping the tens.
Egyptian zero 
In Babylon, the numbering system used base 60. Unfortunately,
since they did not have a symbol for positional zero, the numbers 12=1×60+2= 62; 102=1×60×60+2=3602; 1002=1×60×60×60+2=216,002, were represented in exactly the same way. The Babylonians
do not seem to have been much worried about this.
Maya symbol for zero 
The Greeks, as has been said, did not know the zero. Ptolemy uses in
the Almagest a positional symbol equivalent to zero, but
considers it as a simple annotation, not as a digit that can be treated like
any other. Therefore, the use of his symbol did not spread.
Our positional notation, with a zero equivalent to any other digit, which
can be operated, dates back from the Indian civilization, around the 6th
century. To represent the absence of a digit, they used the Sanskrit word shunya, which means void. The Arabs, who
adopted the Indian notation, transformed that word into sifr. When the notation was transmitted towards
the tenth century from AlAndalus to Western Europe with the name of Arabic
numeration, this word became, on the one hand, zero, on the other cipher.
This book by Clifford Pickover
contains many riddles and anecdotes related to mathematics.
The same post in Spanish
Thematic Thread on Mathematics: Previous Next
Manuel Alfonseca
Hola Manuel,
ReplyDeleteThe anglophone world does not use the apostrophe ' to symbolise multiplication, but either x or * or a central dot, or in algebra simply nothing, so ab means a*b.
Peter
Thanks, Peter, I was aware of that. In fact, I've used the x symbol (not the letter x) and I can see it in my navigator. This must be an incompatibility in yours (perhaps it doesn't have the Symbols font).
DeleteI have replaced the multiplication symbol by an alternative one that I hope works in every navigator. Can you confirm that you can now see it?
Delete