Alan Turing is someone who spent a lot of time thinking about the mystery of consciousness
and what it means to be alive. His work in computing also tackled these questions and
with his ideas about the Turing machine and the Turing test he no doubt brushed
up against the questions of whether a computer could be considered to be alive or conscious
and where a classification would leave the field of artificial intelligence.
As a boy Alan Turing read a book called Natural Wonders by Edwin Tenney Brewster
and he later told his mum that it was this book that opened his heart
and mind to science. The book explores lots of wonderful ideas around the science of life
including questioning aliveness and a chapter on where we do our thinking.
While doing research for this video I enjoyed this book so much that I wanted to read it out to you
and so i've started a podcast doing just that. The first episode about how the chicken gets inside
the egg is up now for everyone and the rest of the episodes will be available through my Patreon.
For now though let's have a look at the chapter called how much of us is alive.
The author talks about how much of a tree could be considered to be alive. The bark is dead
and the wood is dead between the two is a thin layer which is alive. The green leaves are alive
and the twigs but at least half of every living tree is already dead.
The blood we say is the life and yet the blood itself is dead. The watery part is just soup
water and salt and fat and jelly. The minute coin-like red blood corpuscles carry the oxygen
of the air from the lungs all over the body but there are similar oxygen carriers likewise dead
in bottles in the drugstore. Maybe this question of whether our blood is considered alive or dead
could be better left to philosophers but this is the view that the author holds
and he describes us as being made of living bricks but set in a dead mortar.
Perhaps it is the incompleteness of this explanation that inspired Alan Turing
to want to explore how to get from a series of living bricks to intelligence
and Turing did have a lifelong passion for biology. I'll put on screen some pictures
from some of his less known work on the topic of morphogenesis, in trying to understabd
the patterns in living things whether it's in the fur of animals and the patterns and the colors
all the way down to the way the seeds arrange themselves in a flower head. Turing was trying
to understand how this could happen from kind of a mathematical perspective and these ideas are also
particular favorites of mine. I've always been really fascinated by this interface of biology
and maths and finding patterns in nature so I really love having a look at some of this work.
Questioning the nature of aliveness is also something that influenced the way that
Alan Turing approached childhood grief. An important part of the story of Alan Turing's life
is that of his childhood best friend and possibly first love Christopher Morcom.
Alan and Christopher would spend a lot of time together at the Sherborne school library where
they would discuss their ideas in mathematics and science. Christopher was a year older than
Alan and also a very gifted mathematician. He had won a scholarship to study at Cambridge University
but he died in 1930 at age 18 before he was ever able to take up his place.
He died from bovine tuberculosis which came from drinking infected cow's milk
and the loss was really difficult for Turing,
he stayed close with Christopher's mother and wrote her a letter all about his thoughts on the
spirit in which he says that the body provides something for the spirit to look after and use.
It sounds like this was his way of wrapping his head around the loss and also comforting her.
Turing also resolved to work extra hard going forward
to make up for the great potential that had been lost.
Christopher's mum created a science prize at the school to help remember Christopher by and the
very first winner of that prize was Alan Turing, and as part of his prize he got to select a book.
The one he chose was called Mathematical Recreations and Essays.
The last chapter of this book was about cryptographs and
ciphers and it was quite possibly the first place where Turing encountered those ideas.
Eight years later he would be working at the British code breaking organization
and helping to develop solutions to decrypting enigma machine messages.
Now some of these solutions that he was helping to develop
were first worked out by Polish code breakers.
The chapter starts by giving some definitions of a cryptograph and a cipher.
It says here that a cryptograph may be defined as a manner of writing
in which the letters or symbols employed are used in their normal sense
but are so arranged that the communication is intelligible only to those possessing the
key. A simple example is a communication in which every word is spelt backwards.
A cipher may be defined as a manner of writing by characters arbitrarily invented or by an arbitrary
use of letters words or characters in any other than their ordinary sense
intelligible only to those possessing the key. A simple example is when each
letter is replaced by the one that immediately follows it in the natural order of the alphabet
a being replaced by b, b by c and so on finally z by a.
In a communication cipher symbols may be arranged cryptographically and thus further hinder a
reading of the message so the message above as a cryptographic cipher would be this quite confusing
message down here, but of course these messages get much more complicated than these examples.
Later in the chapter the author goes on to talk about cipher machines
he says that there's a risk of some instrument when set falling into unauthorized hands
and this must be taken into account. Since equally good ciphers can be constructed
without the use of a mechanical device I do not think their employment can be recommended.
Now after this was written cipher machines
would go on to become the norm and Alan Turing who read this book would go on to attack the
enigma machine which is an example of one, so perhaps not everything in this book is
totally up to date but both of these books i've mentioned so far are now in the public
domain so you can read them yourself for free and there'll be links in the description to do that.
Of course there are plenty of other books and people who inspired Alan Turing throughout his
life and in his childhood and we can see another resource here which is the complete list of
library books that Alan borrowed while he was a student at the Sherborne school. As mentioned in
my previous video he read a lot of books about math, science, physics and astronomy and not
so many fiction books and his english teacher tried to encourage him to read more of those.
He did read the Alice in Wonderland books which did have a bit of a mathematical bend to them
but I find looking at this list of books that he read as a student to be pretty interesting.
It would seem to me that even when he was young he knew what he was interested in and
he pursued those things he was interested in and eventually found success in them.
Thanks as always to my Patreon supporters
and a special shout out to today's Patreon cat of the day Chito.
Thanks for watching and I hope to see you next time