Why is x the unknown Terry Moore
I have the answer to a question that
we’ve all asked the question is why is
it that the letter X represents the
unknown now I know we learned that in
math class but now it’s everywhere in
the culture the X PRIZE the X Files
Project X TEDx where’d that come from
about six years ago I decided that I
would learn Arabic which turns out to be
a supremely logical language to write a
word or a phrase or a sentence in Arabic
is like crafting an equation because
every part is extremely precise and
carries a lot of information that’s one
of the reasons so much of what we’ve
come to think of as Western science and
mathematics and engineering was really
worked out in the first few centuries of
the Common Era by the Persians and the
Arabs and the Turks this includes the
little system in Arabic called algebra
and algebra roughly translates to the
system for reconciling disparate parts
algebra finally came into English as
Algebra one example among many the
Arabic texts containing this
mathematical wisdom finally made their
way to Europe which is to say Spain in
the 11th and 12th century and when they
arrived there was tremendous interest in
translating this wisdom into a European
language but there were problems one
problem is there there are some sounds
in Arabic that just don’t make it
through a European voice box without
lots of practice trust me on that one
also those very sounds tend not to be
represented by the characters that are
available in European languages here’s
one of the culprits
this is the letter Xin and it makes the
sound we think of as SH it’s also the
very first letter of the word
shailen which means something just like
the English word something some
undefined
unknown thing now in Arabic we can make
this definite by adding the definite
article al so this is Al Shaitan the
unknown thing and this is a word that
appears throughout early mathematics
such as this 10th century derivation of
proofs the problem for the medieval
Spanish scholars who were tasked with
translating this material is that the
letter Sheen and the word Shaitaan can’t
be rendered into Spanish because Spanish
doesn’t have that Sh that sound so by
convention that they created a rule in
which they borrowed the CK sound of the
sound from the classical Greek in the
form of the letter Chi later when this
material was translated into a common
European language which is to say Latin
they simply replaced the Greek Chi with
the Latin X and once that happened once
this material was in Latin it formed the
basis for mathematics textbooks for
almost 600 years but now we have the
answer to our question why is it that X
is the unknown X is the unknown because
you can’t say SH in Spanish and I
thought that was worth sharing