in my memory locked
And you yourself shall keep the key of it"
is a very creative art. In order to decipher any kind of
code it is necessary to employ both logical and analogical
kinds of thought. Analogical thought is intuition gained
by a quick gleaning of a pattern, or a flash of insight
from the subconscious. Both pattern recognition and linear
thought are necessary in code-breaking. Thus, this is an
excellent exercise to train the mind to think using both
halves of the brain.
use of cryptography dates back to the beginning of man's use of
written language. The word cryptography comes from the Greek meaning
hidden writing. The oldest physical examples we have of using written
codes dates back to the Spartan government's use of scytales. These
were special devices in which the sender and recipient each had
a special cylinder of the same size. A ribbon was wrapped around
the cylinder and the message written vertically on the ribbon. The
ribbon was worn as a belt and delivered to the receiver. Once the
receiver wrapped the ribbon on the appropriate cylinder the message
could be deciphered by reading vertically.
few noted cryptographers were:
has become a very important part of computer technology and an integral
part of the Internet. The ability to encrypt and decrypt information
is crucial to secure financial transactions and even elementary
forms of on-line privacy.
our purposes here, we will concentrate on simple ciphers and cryptograms
as an exercise in using both sides of the brain. Intuition plays
a heavy role in the deciphering process. Whether it is recognizing
a pattern in the coded message, or simply remote viewing the cipher
key, those who are adept at code-breaking have always credited their
art to insightful means. While the bulk of deciphering remains in
the analytical realms, the reasoning of the algorithm used to encode
the message, both kinds of thought are useful in breaking a code.
an overview, here is some basic terminology used in the art of code-breaking.
Cryptography is the science of keeping written messages secret.
Cryptanalysis is the art of breaking the cipher, or retrieving the
message without knowing the proper key. Cryptology is the branch
of mathematics that studies the mathematical foundations of cyrptographic
methods, i.e. the algorithms useful in creating codes, both public
and private. A cipher is a method of encryption and decryption.
All ciphers depend upon a key or algorithm to code the message and
make it possible for the intended receiver to decode the message.
are two types of key-based algorithms, symmetric (or secret-key)
and asymmetric (or public-key). The difference is that the symmetric
keys use the same algorithms for encryption and decryption. An asymmetric
algorithm uses a different key for encoding and another for decoding.
Asymmetric ciphers permit the encryption key to be public, allowing
anyone to use the key for encoding. The encryption key is called
the public key and the decryption key the private or secret key.
Computers generate most modern cryptographic algorithms with specialized
hardware and software devices.
cryptograms use two main types of ciphers, a substitution cipher
or a transposition cipher. A substitution cipher replaces individual
letters (singly or in groups) with others within a definite system
and a key. Of this type there are also monoalphabetic and polyalphabetic
ciphers. A monoalphabetic always uses the same letter of the alphabet
for the ciphertext letter. Below is a simple wheel showing the use
of a monoalphabetic substitution
polyalphabetic cipher means that different alphabets were
used to encrypt the message. This is used for more complex
encoding and makes the message harder to decode.
transposition cipher produces a cryptogram in which the original
letters of the message have been rearranged according to a
definite system and key. An example being that each third
word of the message is the key, or a scytale is another example.
The substitution of the alphabet is not used here.
facilitate the art of code breaking well give you some
handy rules of thumb that will help you to see patterns in
the code or to find the key that unlocks the message.
for one-letter words. The word is A nine times out of ten. If
A doesn't work, try I.
three-letter word may be THE especially if it begins the crypogram,
both first and last letters are of high frequency, or the same
three letter word appears more than once.
the first six letters of the frequency alphabet, E, T, A, O,
N, and I. The complete frequency alphabet is:
E T A O N I S R H D L U F C M W P G Y B V K X J Q Z
to identify vowels. One way is to examine how many different
letters adjoin a high-frequency cipher letter. The four most
used vowels, A, E, I, O must touch the 20 consonants more often
than the consonants touch the different vowels. Also, every
sequence of five or six letters most always contains a vowel.
for doubled letters. The most often used doubles are L, E, S,
O and T.
the final letters of the ciphers words. Letters that appear
often as final letters include E, W, T, D, N, R, G, K, and Y.
these helpful hints you are well on your way to solving most cryptograms
that are published today. There is a myriad of encryption methods,
and once you have the method or system you can fairly easily unlock
the key. Intuition is the strongest factor in gaining insight to
a key. Allow your subconscious to scan the ciphered text and quietly
wait for some subtle feelings of how to proceed. Once you've discovered
the key or some important words, logical thought takes over and
you proceed to unravel the algorithm that was used to encrypt the
is another fun way to use both sides of the brain. The Internet
is full of sites that have cryptograms. As you play with this you
may become interested in the science of cryptography itself. Enjoy
the process and create some new neural pathways as a result.
have a special applet created by Jos van Uden that will allow you
to test your cryptographic skills. To use this applet
an in depth study of cryptology as well as a thorough examination
of the controversy of Francis Bacon's authorship of Shakespeare's
plays go to
Penn Leary's site.
J.L. Read, 1997. All Rights Reserved.
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