Author: Jinavie

Posted in History & Literature

Ghoti

Posted on by Jinavie

If the gh sound in “tough” is pronounced “F”,
And the o in “people” makes the short “I” sound,
And the ti in “nation” is pronounced “SH”, 
Then the word “ghoti” is pronounced just like “fish”.

This is the shortcoming of the English language, where so many letters can be pronounced in various ways depending on the context of the word. This problem cannot be found in languages such as Korean where every Hangul character can be pronounced a set way, as they each represent a certain sound.

Therefore, there is no other way of saying “moolgogi (물고기, fish in Korean)” other than just that. This is why the Korean Hangul is a far superior and more logical method of writing than the English alphabet.

Posted in Psychology & Medicine

Fortune Telling

Posted on by Jinavie

A “good fortune teller” is not an “accurate” fortune teller. A “good fortune teller” is a fortune teller who “says good things”. A fortune teller who tells fortunes that are too real, despite warning people of the dangers to come in the future, tends to be ignored and hated on just like Cassandra from ancient Greek mythology. Human beings say they fear uncertainty in the future and want some certainty, but they do not want to hear about an unhappy future. This is a normal response. Who would want to hear that they will soon be diagnosed with a terminal illness, or that they will break up with their lover? However, people are fascinating in that they still try to know the future. We go to fortune tellers and read horoscopes to try figure out what will happen to us. But if they receive bad news such as “you will fail your next exam”, instead of studying even more they curse at the fortune teller for giving them a bad prediction. Thus, human beings live among curiosity about their life and fear of the unknown future, while celebrating good fortunes and actively denying bad ones.

The reason why we like to have our fortunes read is similar to why we watch previews of television shows: we are curious about what will happen. But if you ponder this deeply, you soon come to a great epiphany. The further you look out into the future, the clearer this becomes. Everyone eventually dies. A person’s life span is typically not much longer than a hundred years, with everyone meeting the same fate some day.

A fortune teller predicts the ups and downs of a person’s life. If you think about it, life is composed of a series of peaks and troughs that eventually result in death. No matter what misfortune comes your way, it will pass just as seasons come and go. A person who passed an exam is happy and leads a good life, but even if the person fails, they somehow make it through. Unless you give up, a person will continue to live on. C’est la vie. Life is as simple as that.

If the best fortune teller in the history of mankind told your fortune, they would say the following: “nothing matters, live the way you want”. Whether your fortune for the week is good or bad, you will eventually die. There is no point scaring yourself with fortunes, live every day as if it was your last. An uncertain future may be scary, but it also represents infinite possibilities. Just like Schrödinger’s cat, our tomorrows are both alive and dead at the same time. Until tomorrow comes and the box is open, we can never know what the future holds.

So as long as it does not harm you or anyone else, do whatever the hell you want.

Posted in Science & Nature

Cryptography: Book Cipher

Posted on by Jinavie

So far, the three ciphers introduced could all easily be cracked using frequency analysis and the Kasiski examination. Is there a cipher that is easy to implement yet difficult to break for a beginner cryptanalyst? An extremely popular and surprisingly powerful cipher is the book cipher. Essentially, the book cipher replaces a keyword with an entire book. Instead of replacing a letter for a letter or symbol in a systematic and mathematical way (such as a set shift number or using a tabula recta), the book cipher replaces letters for numbers that refer to a certain text within a book. As the only way to decode the message is to have the book, it is an extremely secure way of enciphering a message given that both parties have an identical copy of the book.

There are many variations of the book cipher. The most popular type is giving a page number, with the first letter of the page being the plaintext. A variant of this is giving a set of three numbers for every letter: the page number, the line number and the word number (or just two: page and line, then take the first letter). Ironically, this may be less secure at times as it may reveal that it is a book cipher. However, doing this for each letter makes the enciphering and deciphering process incredibly long and arduous.

A shortcut method is to refer to a word within a page (using the three-number set coordinates method described above) to shorten the ciphertext. Although this method is much easier in practice, it poses the challenge of finding a book that includes all the words in the plaintext, which may be difficult if the code is for military or espionage purposes.

Because of this, and the fact that both parties (or everyone in the ring) need identical versions of the book while not standing out too much, the most common books used are the dictionary (typically a famous version such as the Oxford Dictionary) or the bible (again, a standard version is used). These books are not only good because they incorporate a massive vocabulary, but they are also inconspicuous while being carried around in an enemy territory.

The book cipher is a very difficult code to crack for most people without advanced cryptanalysis training. Thus, the easiest way to crack is to deduce what book is the keytext. There are numerous ways to do this, but one way would be to cross-match the books of two known spies until common books are found. In the setting of spies in a foreign country, a book such as a traveller’s guide or phrasebook dictionary can be considered a likely target as it can be carried around easily while containing many words. Ergo, the secret behind cracking the book cipher is less about cryptography and more about using the science of deduction.

Posted in Science & Nature

Cryptography: Kasiski Examination

Posted on by Jinavie

The Kasiski examination can be used to attack polyalphabetic substitution ciphers such as the Vigenère cipher, revealing the keyword that was used to encrypt the message. Before this method was devised by Friedrick Kasiski in 1863, the Vigenère cipher was considered “indecipherable” as there was no simple way to figure out the encryption unless the keyword was known. But with the Kasiski examination, even the Vigenère cipher is not safe anymore.

The Kasiski examination is based on the fact that assuming the number of letters of the keyword is n, every nth column is encoded in the same shift as each other. Simply put, every nth column can be treated as a single monoalphabetic substitution cipher that can be broken with frequency analysis. Ergo, all the cryptanalyst needs to do to convert the Vigenère cipher into a Caesar cipher is know the length of the keyword.

To find the length of the keyword, look for a string of repeated text in the ciphertext (make sure it is longer than three letters). The distance between two equal repeated strings is likely to be a multiple of the length of the keyword. The distance is defined as the number of characters starting from the last letter of the first set of strings to the last letter of the second set of strings (e.g. “abcdefxyzxyzxyzabcdef” -> “abcdef” is repeated” -> distance is “xyzxyzxyzabcdef” which is 15 letters). The reason this works is that if there is a repeated string in the plaintext and the distance between these strings is a multiple of the keyword length, the keyword letters will line up and there will be repeated strings in the ciphertext also. If the distance is not a multiple of the keyword length, even if there is a repeated string of letters in the plaintext, the ciphertext will be completely different as the keyword would not match up and be different.

It is useful recording the distance between each set of repeated strings to find the greatest common factor. The number that factors the most into all of these distances (e.g. 6 is a factor of 6, 12, 18…) is most likely the length of the keyword. Once the length of the keyword is found, then every nth letter must have been encrypted using the same letter of the keyword. Thus, by recording every nth letter in one string, you can obtain what is essentially a Caesar cipher. The Caesar cipher is then attacked using frequency analysis. Once a few of these strings (of different positions on the ciphertext) are solved, the keyword can be revealed by checking the shift key against a tabula recta (e.g. if a certain string of nth letters is found to have been shifted 3 letters each, then the corresponding letter in the keyword must be “D”, which shifts every plaintext letter by 3 in the Vigenère cipher). When the keyword is deduced, every message encrypted using that keyword can now easily be decoded by you.

Although the Kasiski examination appears to be complex, attempting to try it reveals how simple the process is. Thus, it is useful to try encrypting a message using the Vigenère cipher then trying to work out the keyword using the Kasiski examination. Much like the frequency analysis, it is an extremely useful tool in the case of needing to break a secret code.

Posted in Science & Nature

Cryptography: Vigenere Cipher

Posted on by Jinavie

It has thus been proven that the Caesar cipher, the pigpen cipher and any substitution cipher can be simply broken using frequency analysis. The basis for this is that each letter or symbol can only represent a single letter, meaning that letter frequencies (e, t, a, o…) are directly translated onto the cipher language. Ergo, by making each letter represent more than one letter, the letter frequencies can be masked and an additional level of security can be added to the cipher. This is called polyalphabetic substitution and it is the basis for a type of cipher known as the Vigenère cipher.

The cipher was first conceived in 1553 by Giovan Battista Bellaso and has been improved since. It is famous for being rather simple to use despite the difficult to decipher it at a beginner’s level. This trait earned the cipher the nickname “le chiffre indéchiffrable”, which is French for “the indecipherable cipher”.

The Vigenère cipher can be thought of a stack of Caesar ciphers (essentially a cipher within a cipher), where each letter is shifted by a variable key (in a normal Caesar shift, every letter is shifted by the same key). This is achieved by the implementation of a keyword and a table called a tabula recta. A tabula recta is simply a grid made from 26 rows of the alphabet, each row of which is made by shifting the previous one to the left. This table essentially shows all the possible outcomes of a Caesar shift.

Now, let us try encoding a message using the Vigenère cipher. The message “attack at dawn” is encoded using the keyword “nothing”. Ideally, there should be no repeating letters in the keyword for the sake of security. Therefore, if there are any repeating letters, just remove the repeated letters (e.g. “crocodile” -> “crodile”). First, repeat the keyword until it matches the number of letters of the message (e.g. “attackatdawn” is aligned with “nothingnothi”). Then, use the tabula recta to encrypt the message. The rule of thumb is “key-row, message-column”, meaning that the row of the tabula recta starting with the letter of the key is matched against the column starting with the respective letter of the message. To take the first letter as an example, the key letter is “n” and the message letter is “a”. The letter corresponding to where the “n” row and “a” column meets is “N”. If this rule is followed for each letter, the encrypted message becomes: “NHMHKXGGRTDV”. Although it takes some effort to find each letter on the table, the message becomes “indecipherable” to a beginner cryptanalyst as frequency analysis becomes useless. For example, the repeating letter “H” can represent either “t” or “a”. The longer the keyword is, the more secure the Vigenère cipher becomes.

However, the Vigenère cipher is not indecipherable. Next, we will look at a cryptanalysis method called the Kasiski examination that attacks a polyalphabetic cipher such as the Vigenère cipher to gain access to the keyword.

Posted in Science & Nature

Cryptography: Pigpen Cipher

Posted on by Jinavie

Another well-known substitution cipher is the “pigpen cipher” or “Freemason’s cipher”. As the name suggests, it was often used by Freemasons to encrypt their messages. However, as time has passed, it has become so well-known that it is not a very secure cipher at all.

The pigpen cipher does not substitute the letter for another letter, but instead uses a symbol that is derived from a grid-shaped key. The key is made of two 3×3 grids (#)(one without dots, one with dots) and two 2×2 grids (X)(one without dots, one with dots). The letters are filled in systematically so that each shape represents a certain letter (e.g. v=s, >=t, <=u, ^=v)

The cipher has many variations that attempt to throw off an attacker by rearranging the order of the grids or the letters. Thus, even if a cunning attacker picks up on the fact that the cipher is a pigpen cipher, they may use the wrong key and get a completely wrong message. Nonetheless, it is a useful skill to recognise the unique symbols of the pigpen cipher as it is a popular cipher used commonly in puzzles.

As with any substitution ciphers, frequency analysis and pattern recognition is the key to cracking the pigpen cipher.

Posted in Science & Nature

Cryptography: Caesar Cipher

Posted on by Jinavie

One of the earliest known uses of cryptography can be traced back to ancient Rome. Julius Caesar was well-known for his use of a type of substitution cipher dubbed “Caesar cipher” or “Caesar shift”. The encryption is very simple: shift every letter a certain value down the alphabet (the value is known as the key). For example, Caesar used a key of 3 to encrypt his messages to his general, so the message “ATTACK AT DAWN” would be encrypted into “DWWDFN DW GDZQ” (use the scheme of a=0, b=1, c=2, d=3…).

Although it was an efficient encryption system in ancient times, since then it has been revised to be much more secure. The Caesar cipher has thus been demoted to the preferred code used by children and teenagers for basic decoding puzzles.

Due to the simplicity of the encryption, cracking the Caesar cipher is quite easy with the use frequency analysis, pattern recognition and brute force analysis. Brute force analysis can be used if the attacker knows that a Caesar cipher has been used. If that is the case, the message can be decrypted using every possible key (e.g. 1, 2, 3…) until a message that makes sense is acquired.

Posted in Science & Nature

Cryptography: Frequency Analysis

Posted on by Jinavie

A cipher is a message that has been encoded using a certain key. The most common and basic type of ciphers are encrypted using letter substitution, where each letter represents a different, respective letter. For example, the message may be encoded in a way so that each letter represents a letter three values before it on the alphabet (e.g. if a=0, b=1… “a” becomes “d”, “b” becomes “e” etc.). This creates a jumble of letters that appears to be indecipherable.

However, the characteristics of substitution ciphers make them the most decipherable type of encryptions. As each letter can only represent one other letter, as long as the key is cracked (i.e. what letter is what), the message and any future messages can be cracked. The most important tool in decrypting substitution ciphers is pattern recognition and frequency analysis.

Frequency analysis relies on the fact that every language has certain letters that are more used than others. In the English language, the letters that are most used, in order, are: E, T, A, O, I, N, S, H, R, D, L, U (realistically, only E, T, A, O are significant and the rest are neither reliable nor useful in frequency analysis).

For example, if Eve intercepted a long, encrypted message that she suspects to be a simple substitution cipher, she will first analyse the text for the most common letter, bigram (two letter sequence) and trigram. If she found that I is the most common single letter, XL the most common bigram and XLI the most common trigram, she can ascertain with considerable accuracy that I=e, X=t and L=h (“th” and “the” are the most common bigram and trigram respectively). Once she substitutes these letters into the cipher, she will soon discover that certain patterns arise. Eve may notice words such as “thCt” and deduce that C=a, or find familiar words and fill in the blanks in the key. The discovery of each letter leads to more patterns and the vicious cycle easily breaks the code.

Frequency analysis is extremely useful as it can be used to attack any simple substitution ciphers, even if they do not use letters. For example, in Sir Arthur Conan Doyle’s Sherlock Holmes tale The Adventure of the Dancing Men, Sherlock Holmes uses frequency analysis to interpret a cryptogram showing a string of hieroglyphs depicting dancing men.

To reinforce this weakness in substitution ciphers, many cryptographers have devised better encryption methods such as polyalphabetic substitution, where several alphabets are used (e.g. a grid of two alphabets – also called a tabula recta).

Posted in Psychology & Medicine

The Desire Of Others

Posted on by Jinavie

This world endlessly tells us to live for the desires and wants of others. We live every day to fulfil the desire of our parents, our teachers, our friends and our lovers. But to live for other people’s desired, you must first fulfil your own desires. For our weak “self” identity to survive and develop, we cannot allow other people’s desires dominate us.

There is a mental illness called delusional disorder where the patient is obsessed about a “false belief” and is completely convinced that it is the truth. The word “delusion” brings to mind strange cases such as “I was abducted by aliens” and “the government is monitoring my phone calls”, but these delusions are more common with conditions such as schizophrenia. Instead, delusional disorder presents with delusions such as Othello syndrome (believing your spouse is having an affair) or hypochondria that are not too strange and allows for a relatively normal day-to-day life, making delusional disorder very hard to detect. Furthermore, the patients form these delusions in a very logical and highly structured manner, causing the patient to become easily obsessed with it and make the delusions more believable.

Delusional disorder can be categorised into six types:

  • Erotomanic type: delusion that someone is in love with you
  • Grandiose type: delusion that you are godlike and possess greater value, strength, intelligence or identity than others
  • Jealous type: delusion that your lover is unfaithful
  • Persecutory type: delusion that someone is acting malevolently or trying to harm you
  • Somatic type: delusion that you have a medical condition or physical defect
  • Mixed type: delusion showing characteristics of more than one of the above types, with no one type being prominent

As these patients are so attached to their delusions, treatment is extremely difficult. As soon as a psychiatrist or psychologist attempts treatment or even a close friend denies the delusion, they instantly become an “enemy”. The patient automatically incorporates those people into their delusion and antagonise them to worsen the situation. This is why the key principle of treating delusion is “do not touch the delusion”. For example, if the patient believes they are someone else, instead of negating that delusion you should give them a chance to be that person. A treatment called “psychodrama” uses impromptu acting to bypass the delusion and tries to reach the patient’s subconscious, or their “self”. Through this, one can approach the patient’s “self” via affirming their delusions, allowing the psychiatrist or psychologist to ask what the patient’s “self” wants and discover the source of the delusion. The important point is that this treatment is not an instant cure for the delusions (it takes a while for the patient to rid themselves of the delusions completely).

Delusional disorder is a phenomenon which is not uncommon in people who live for the desires of others. A perfect example would be young celebrities. If young teenagers begin life in the entertainment sector and live for the audience before they develop their own “self”, they may not be able to find answers to questions such as “who am I” and “what do I want”, ultimately causing a weakening of their identity. As the “self” is highly capable of tricking itself, it creates a delusion that can rationalise this situation and works to create a different identity.

Thus, the most important tool for surviving in this world is not money, power, wisdom or love: it is your identity and “self”. If you do not know what you truly want, then life cannot give you happiness and success.