# Nines (Was Re: yuga, VarNa and colour)

Gregory {Greg} Downing downingg at is2.nyu.edu
Mon May 19 13:42:51 UTC 1997

```At 02:18 PM 5/19/97 BST, you (jacob.baltuch at euronet.be (Jacob Baltuch)) wrote:
>>Actually the digits of any number that is a multiple of 9 will have a
>>sum of 9 as well.
>
>Not true: 9 * 11 = 99
>

I think what was meant was that if you start with 99, then 9 + 9 = 18 and 1
+ 8 = 9. I.e., supposedly all numbers that are multiples of nine will "add
down" to nine if you make sums of their component digits till you get to a
single-digit number. But I do not know anything remotely like enough math
theory to say that this is true in all cases, or if so why.

As long as I'm on for a moment, I suspect the important thing
(culture-historically) about nine might be its status as a cube of three and
maybe its status as the proportion between cycles of moon/menstruation and
the average human gestation period. Three is connected to this aspect of
nine in that sexual reproduction involves three (two parents and a child;
"and baby makes three" as the old song goes). That is the case anyway in
Chap. 14 of Joyce's Ulysses, set in a maternity hospital, where threes and
nines figure prominently.

The neoplatonist Plotinus's Enneads (from the Greek for nine) is a treatise
of philosophical and metaphysical analysis set up in nine books. Etc....

Greg Downing/NYU
greg.downing at nyu.edu
or
downingg at is2.nyu.edu

```