Posted in Psychology & Medicine

Pick A Card

A very common card trick involves the magician asking you to pick a card as he ripples through a deck of playing cards in front of you. Following a few misdirects, such as pretending to pick out the wrong card and burning it, the magician will reveal the card that you chose secretly in your head. How did they do this?

The solution to the trick is to simply trim the top of a card and placing it in front of a card that the magician chose ahead of time. Because of the small gap, the chosen card ends up being revealed longer than other cards to the person as the deck is being rippled. That slight increase in visibility makes it much more memorable, subtly nudging the person towards choosing it.

As simple as the trick may be, it highlights how often we are under the illusion of choice. As much as we hate to admit it, we are quite susceptible to suggestion and persuasion. This is the basis of subliminal messaging, hypnosis and many types of mentalism (magic tricks involving manipulation of the mind). When we make a choice, how do we know that it comes purely from our own free will and volition?

Take for example the phenomenon of fake news. One of the dangers of fake news is that by using provocative, misleading headlines and summaries, it grabs our attention and leaves an impression. This means that unless we are vigilant about fact-checking and reading news from reputable sources, we can easily be manipulated into thinking or acting in a way that benefits those who released the fake news. The results of this may range from benign, such as persuading you to choose a certain brand of product over another, to something as sinister as affecting how you vote in an election or creating discord amongst the population of a country.

The field of psychology constantly reminds us of how flawed our minds are, with its numerous cognitive biases and ways it can be manipulated. We must be constantly aware of this fact to prevent ourselves from falling victim to those who try to take advantage of our thoughts and actions.

Posted in Science & Nature

Card Shuffling

Take a standard deck of playing cards. Shuffle it thoroughly and set it on the table. Consider this: what is the probability that the order those 52 cards are in is the same as the order of a deck shuffled by someone else? The answer can be found using a simple maths equation: 52!

! denotes a factorial, where you multiply the number to every other positive integer smaller than it. For example, 5! = 5 x 4 x 3 x 2 x 1 = 120. Due to its nature, factorials grow rapidly – even faster than exponentials. For example, 10! is 3.6 million and 15! is 1.3 quadrillion. By 52!, the number grows to:


This number is so big that if every star in our galaxy had a trillion planets, each with a trillion people living on it, all shuffling a trillion deck of cards at the rate of 1000 shuffles per second, since the beginning of time, only now would someone have a deck that is in the exact order as your deck.

Ergo, you can say with absolute, mathematical certainty, that the deck you have shuffled is in an order never created by any human being in the history of the world.


Posted in History & Literature

Playing Cards

Playing cards are the basis of so many games due to their diversity and adaptability. It can be used for any game from poker to the Eleusis game, from house of cards to magic tricks.
One thing that is often overlooked is the long history of cards and the various symbolisms hidden within. For example, the suits may have the following symbolism:

Spades            Nobility, swords, war
Hearts             Church, cups, love and romance
Diamonds    Merchants, coins, wealth
Clubs               Peasants, clubs/batons, agriculture

Although there are many debates regarding this issue, there is substantial evidence that the court cards (Kings, Queens and Jacks/Knaves) are based on historical or mythical heroes and heroines, at least for the French deck that is commonly used nowadays. The following is the list of presumed models for each card:

King of Spades                David (biblical hero)
King of Hearts                Charlemagne (great king of Franks)
King of Diamonds        Julius Caesar (great Roman emperor)
King of Clubs                   Alexander the Great (the king of Macedon)

Queen of Spades             Joan of Arc (the French heroine) or Athena (the goddess of war)
Queen of Hearts             Judith (either the biblical heroine or the tragic queen of Bavaria)
Queen of Diamonds    Rachel (wife of Jacob in the bible – he waited 14 years for her)
Queen of Clubs               Argine (anagram of regina, Latin for queen) or Hera (queen of gods)

Jack of Spades                Holger Le Danois (knight of Charlemagne)
Jack of Hearts                La Hire (comrade of Joan of Arc, member of Charles VII’s court)
Jack of Diamonds       Hector (the hero of the Trojan War or the knight of Charlemagne)
Jack of Clubs                  Lancelot (King Arthur’s most trusted knight)

Although the models for the Kings and Jacks are quite clear, the Queens are still subject to many discussions. As modern playing cards originate from France circa 15th century, the above models (official names for each card back then) appearto be valid.
This also explains the ordering of suits (spades/nobility first, clubs/peasants last, hearts/church second and diamonds/merchants third) and how the Ace sometimes trumps the King (possibly symbolising how peasant hold the power, as in the French Revolution).

Sometimes, knowing the history behind a game can make it even more fun.

Posted in Life & Happiness

Eleusis Game

The victory condition for this card game, named after an ancient Greek city, is quite simple: discover the pre-determined law via induction.
This game needs at least four people, with one person acting the position of God. God decides on a certain law (in the form of a single statement) and writes it down on a paper, thus creating the way of the universe
Next, the deck of cards is split evenly between the other players, then one person places a card in the centre. After “the world begins to exist”, God looks at the card and says “This card qualifies” or “This card fails”. The next player also places a card in the centre and the God judges whether it fits the way of the universe.

Players carefully study which cards qualify or fail to try discover the way of the universe. If someone thinks they figured the law out, he or she proclaims themself as the prophet, who begins to take over the role of God to announce whether the cards qualify or not. If at any point the prophet is wrong, he is dismissed. If the prophet correctly judges ten cards in a row, he states his hypothesised law and compares it to the piece of paper. The prophet wins if the two laws coincide, but is dismissed if it is not. When all 52 cards are played without a successful prophet, God becomes victorious.

However, as this is a game, the way of the universe cannot be too complex. To make it fun, the God player must devise a law that is simple yet difficult to discover. For example, the law “Alternate a card higher than 9 and a card lower than 9” is tricky as players tend to focus on picture cards or the colours of the cards. Also, laws such as “Only red cards qualify, except the tenth and thirtieth cards are disqualified” and “Accept all cards that are not the 7 of Hearts” are illegal, as they are too detailed. A God who comes up with such ways of the universe that cannot be found using logic and the scientific method loses his right to play the game. Ergo, the God must seek simplicity that is not easily conceived.

So what is the most successful strategy for this game? Even if there is the risk of being dismissed, proclaim yourself as the prophet as soon as possible for the best chance of winning.