This reminds me of a self-working trick I saw online in the 90s.

The website shows you a hand of 5 cards, and asks you to pick one card and stare at it intensely. It claims it will read your mind and guess the card. When ready, you will click a button, and 5 new cards are shown - 4 random cards plus the card you thought of.


The trick is that the same cards are shown as before, but in different order. Most people only focused on the one card and don't notice that the rest of the cards are the same. It sounds very simple, but it worked on me and all my family members, at least the first time.

It seems like the basic descriptions of these two tricks, the cards and the liquids, are terribly vague and imprecise in this article, so it's difficult to discuss it. In particular, it's unclear what information is shared, and what information is hidden.

The logical and mathematical analysis later in the article looks more detailed, but unfortunately the initial, fundamental, description of the process lacks clarity and forces us to guess the details

Just performed this trick for my partner and she was very underwhelmed. There’s probably a good delivery to figure out.
The wine and water explanation doesn’t make sense to me. Wine and water have different molar masses and combining a liter of water and a liter of wine doesn’t give exactly two liters of the new substance, in the same way as a liter of ping pong balls and a liter of sand doesn’t produce two liters of ping pong sand when mixed together - some of the molecules are bigger than some of the others.

Once you pour a liter of the new, mixed, wine-water substance back into the first container, you’ll likely have less than a liter in the second container, so the wine bottle will contain more than the container originally containing water. Right?

The site has more tricks up its sleeve. Right-clicking on mathematical equations brings up a MathJax context menu!
Lol cool. I wonder if some of these types of card-tricks methods - based on "math and shuffle-rounds etc" to get a desired "result/order", can be used in a type of DB-Indexing ?

There must a 100+ of these types of tricks or algo's

I'm always amazed at that a 52 card deck can be arranged in 8x10^67 different ways.
https://web.archive.org/web/20211122214741/https://chalkdust... since it has the Hacker News hug of death.

This is such a ridiculously obvious trick I'm surprised any audience is impressed by it. But that happens for me with a lot of magic tricks... I guess a lot of people just choose to shut off basic thinking (and in this case don't have an intuitive understanding of conserved quantities).