Constrained writing techniques can be used to hide a message in a seemingly innocent letter. While those who write messages with constrained writing do so sometimes as a recreation on rainy days or for the mental propensity to the challenge of composing and decoding the message, this technique can also be used in more serious situations, such as that of a prisoner who he wants to communicate inhuman treatment by his captors when his outgoing mail is scanned and censored.
Normal encryption methods are unsatisfactory, since too explicit a code would simply be thrown away by the jailers without even bothering to crack it. Even without prior communication, a person may be able to compose a message subtle enough to go unnoticed by censors, but unusual enough to be noticed and possibly decrypted by the recipient. The basic assumption is that the recipient is familiar with the author's "normal" writing style, with its internal references, and / or that he is more obstinately seeking a secondary meaning. For example, a hostage minister of worship might be able to refer to phrases from his Sunday sermons that would be known only to his congregation, but not to the Gulag in Siberia.
Steps
Method 1 of 1: Send Your Secret Message
Step 1. Decide which secret message you want to send
It will probably have to be shorter than the full letter. A long message hidden in a short letter limits your writing to the point that it won't feel natural. This undertaking requires a lot of balance. The longer your message on the surface is related to the secret one, the easier it will be to write it and the harder it will be to find it, both from friends and enemies.
Step 2. Choose an encoding method
There is a myriad of possibilities and most of them have several variations. Some are described below, but if you need maximum security, don't use them (nor, of course, any of the methods described online). Originality is the key to safety.
- Acrostics are probably the best known example. In an acrostic, the secondary message is read by taking the first letter of each line (or sentence, etc.). Acrostics are generally easy to both dial and spot.
- Use numbers to code the letters. There are a few ways to do this, including A = 1 Z = 26, ASCII, atomic numbers, or any other well-known number list. An advantage of this method is that numbers can often be entered as plain text without raising suspicions, such as dates and times. Or, there are also many ways of converting words to numbers allowing for more subtle entries. "Well known" refers to the writer and the audience to whom it is addressed: a professor of art history at the University of Illinois would know that "from realism to post-impressionism" corresponds to his course number 441, but an audience generic would ignore it, while a Greek historian would know how to recognize and convert Attic numeration into Arabic numerals.
- Take every nth letter. Of course, more complicated sequences could be used instead of arithmetic. A risk of this method is that it is very delicate. Even adding or removing a single letter can change the rest of the message. With other methods, the message can be reconstructed even if a substantial part is missing, correct or illegible.
- Use words with unusual properties. On a qwerty keyboard, "triple", "galosh", "partier" and "pitied" can almost be typed with a single row of letters. If the misplaced letter is identified, these words encode "LOAD". Any words that do not satisfy this property are ignored.
- Use unnatural letter frequencies. In everyday language there are a few sentences that contain a uniform number of almost any letter (25 or 26) and each can be used to identify the misplaced letter.
- Make mistakes. Spelling mistakes made by a highly educated person who wouldn't normally make them indicate that such mistakes are intentional. Spelling errors can be placed very easily so that you can use any letter you want for the secret message.
Step 3. Consider combining multiple methods to make a complex one
However, there is a risk that if the secret message is hidden too well it may never be discovered. Or, if discovered, it could be so contrived as to suggest that it is a coincidence rather than a deliberate signal. As an analogy, think of one of the criticisms leveled at the controversial biblical code. Although deep messages were found, there is no irrefutable evidence that they were entered on purpose. The methods used, when applied to a sufficiently long text, produced equally profound messages. Encode a secret message by taking each firstto letter may be too weak a signal in itself, but it could be amplified by adding a few passages. Using an acrostic to write "Just the letters, skip the spaces and punctuation" might help in the count and at the same time say aloud, "There is a message here. Keep trying!". Mentioning numbers, all primes, unusually often in the surface text, could direct readers to the correct sequence. The word "prime" could be used frequently in non-numeric contexts in the surface text, and / or encoded according to another method.
Step 4. Depending on the method, you may also need to choose the grain
That is to say, how big is the part of the secret message that you are unveiling at one time. For example, an acrostic usually takes the first letter of each sentence, but could also take a longer train of words or even the first word. Choosing a level consisting of one word or a larger one could cause problems. If the prisoner wants to tell his family that he is being mistreated, he may have difficulty getting the word "waterboard" through the censorship, regardless of the context. He is more likely to be successful spelling it out letter by letter.
Step 5. Carefully compose the surface message around the secret message
Ideally, the surface will look like completely natural writing, so as not to arouse suspicion. Even if the secret message cannot be revealed by the interceptor, it could still be destroyed or corrupted if the existence of such a message is suspected. Realize that this will not be possible if the density of the secret message is high enough, but take a bold attempt, natural enough to fool someone unfamiliar with your usual writing style. It should not include sensitive subjects that can be censored, nor should it contain random or superfluous characters that might raise the suspicion that it is a coded message. A dictionary or vocabulary could be helpful in writing a natural sentence through a difficult restriction. In some cases, some computer programs can be of great help.
Step 6. Answer the same way
If the recipient is able to decrypt the message, a clear way of communicating that both messages have been received is to reply using the same code.
Advice
- As another example, there may be a hidden message in this same article. If the editors responsible for improving this article do their job, it won't stay intact for long, so if you want to find it, be sure to search the original version.
- If you know that, for whatever reason, you will need to communicate secretly with someone, consider agreeing on a binding writing code well in advance. It can be particularly useful for people who perform jobs that expose them to a high level of danger, such as soldiers, correspondents in war zones, and volunteers in areas of civil unrest.
- Type it in Microsoft Word and print it.
