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🔗 Film 🔗 Television 🔗 Novels 🔗 Screenwriters

In fiction, a MacGuffin (sometimes McGuffin) is an object, device, or event that is necessary to the plot and the motivation of the characters, but insignificant, unimportant, or irrelevant in itself. The term was originated by Angus MacPhail for film, adopted by Alfred Hitchcock, and later extended to a similar device in other fiction.

The MacGuffin technique is common in films, especially thrillers. Usually, the MacGuffin is revealed in the first act, and thereafter declines in importance. It can reappear at the climax of the story but may actually be forgotten by the end of the story. Multiple MacGuffins are sometimes derisively identified as plot coupons.

🔗 Languages

The Dolgopolsky list is a word list compiled by Aharon Dolgopolsky in 1964. It lists the 15 lexical items that have the most semantic stability, i.e. they are the 15 words least likely to be replaced by other words as a language evolves. It was based on a study of 140 languages from across Eurasia.

The words, with the first being the most stable, are:

1. I/me
2. two/pair
3. you (singular, informal)
4. who/what
5. tongue
6. name
7. eye
8. heart
9. tooth
10. no/not
11. nail (finger-nail)
12. louse/nit
13. tear/teardrop
14. water
15. dead

The first item in the list, I/me, has been replaced in none of the 140 languages during their recorded history; the fifteenth, dead, has been replaced in 25% of the languages.

The twelfth item, louse/nit, is well kept in the North Caucasian languages, Dravidian and Turkic, but not in other proto-languages.

🔗 Computing 🔗 Computer science

In computational complexity and optimization the no free lunch theorem is a result that states that for certain types of mathematical problems, the computational cost of finding a solution, averaged over all problems in the class, is the same for any solution method. The name alludes to the saying "no such thing as a free lunch", that is, no method offers a "short cut". This is under the assumption that the search space is a probability density function. It does not apply to the case where the search space has underlying structure (e.g., is a differentiable function) that can be exploited more efficiently (e.g., Newton's method in optimization) than random search or even has closed-form solutions (e.g., the extrema of a quadratic polynomial) that can be determined without search at all. For such probabilistic assumptions, the outputs of all procedures solving a particular type of problem are statistically identical. A colourful way of describing such a circumstance, introduced by David Wolpert and William G. Macready in connection with the problems of search and optimization, is to say that there is no free lunch. Wolpert had previously derived no free lunch theorems for machine learning (statistical inference). Before Wolpert's article was published, Cullen Schaffer independently proved a restricted version of one of Wolpert's theorems and used it to critique the current state of machine learning research on the problem of induction.

In the "no free lunch" metaphor, each "restaurant" (problem-solving procedure) has a "menu" associating each "lunch plate" (problem) with a "price" (the performance of the procedure in solving the problem). The menus of restaurants are identical except in one regard – the prices are shuffled from one restaurant to the next. For an omnivore who is as likely to order each plate as any other, the average cost of lunch does not depend on the choice of restaurant. But a vegan who goes to lunch regularly with a carnivore who seeks economy might pay a high average cost for lunch. To methodically reduce the average cost, one must use advance knowledge of a) what one will order and b) what the order will cost at various restaurants. That is, improvement of performance in problem-solving hinges on using prior information to match procedures to problems.

In formal terms, there is no free lunch when the probability distribution on problem instances is such that all problem solvers have identically distributed results. In the case of search, a problem instance in this context is a particular objective function, and a result is a sequence of values obtained in evaluation of candidate solutions in the domain of the function. For typical interpretations of results, search is an optimization process. There is no free lunch in search if and only if the distribution on objective functions is invariant under permutation of the space of candidate solutions. This condition does not hold precisely in practice, but an "(almost) no free lunch" theorem suggests that it holds approximately.

🔗 Military history 🔗 Military history/Intelligence 🔗 Military history/World War II

Operation Mincemeat was a successful British deception operation of the Second World War to disguise the 1943 Allied invasion of Sicily. Two members of British intelligence obtained the body of Glyndwr Michael, a tramp who died from eating rat poison, dressed him as an officer of the Royal Marines and placed personal items on him identifying him as the fictitious Captain (Acting Major) William Martin. Correspondence between two British generals that suggested that the Allies planned to invade Greece and Sardinia, with Sicily as merely the target of a feint, was also placed on the body.

Part of the wider Operation Barclay, Mincemeat was based on the 1939 Trout memo, written by Rear Admiral John Godfrey, the director of the Naval Intelligence Division, and his personal assistant, Lieutenant Commander Ian Fleming. With the approval of the British prime minister, Winston Churchill, and the American military commander in the Mediterranean, General Dwight D. Eisenhower, the plan began by transporting the body to the southern coast of Spain by submarine and releasing it close to shore, where it was picked up the following morning by a Spanish fisherman. The nominally neutral Spanish government shared copies of the documents with the Abwehr, the German military intelligence organisation, before returning the originals to the British. Forensic examination showed they had been read and Ultra decrypts of German messages showed that the Germans fell for the ruse. German reinforcements were shifted to Greece and Sardinia before and during the invasion of Sicily; Sicily received none.

The full effect of Operation Mincemeat is not known, but Sicily was liberated more quickly than anticipated and losses were lower than predicted. The events were depicted in Operation Heartbreak, a 1950 novel by the former cabinet minister Duff Cooper, before one of the intelligence officers who planned and carried out Mincemeat, Ewen Montagu, wrote a history in 1953. Montagu's book formed the basis for the 1956 British film The Man Who Never Was. A second British film was released in 2021, titled Operation Mincemeat. It also has been adapted into a musical.

🔗 India 🔗 Board and table games

Ganjifa, Ganjapa or Gânjaphâ, is a card game and type of playing cards that are most associated with Persia and India. After Ganjifa cards fell out of use in Iran before the twentieth century, India became the last country to produce them. The form prevalent in Odisha is Ganjapa.

🔗 Electronics 🔗 Guild of Copy Editors

The capacitor plague was a problem related to a higher-than-expected failure rate of non-solid aluminum electrolytic capacitors, between 1999 and 2007, especially those from some Taiwanese manufacturers, due to faulty electrolyte composition that caused corrosion accompanied by gas generation, often rupturing the case of the capacitor from the build-up of pressure.

High failure rates occurred in many well-known brands of electronics, and were particularly evident in motherboards, video cards, and power supplies of personal computers.

🔗 Mathematics 🔗 Game theory

The angel problem is a question in combinatorial game theory proposed by John Horton Conway. The game is commonly referred to as the Angels and Devils game. The game is played by two players called the angel and the devil. It is played on an infinite chessboard (or equivalently the points of a 2D lattice). The angel has a power k (a natural number 1 or higher), specified before the game starts. The board starts empty with the angel at the origin. On each turn, the angel jumps to a different empty square which could be reached by at most k moves of a chess king, i.e. the distance from the starting square is at most k in the infinity norm. The devil, on its turn, may add a block on any single square not containing the angel. The angel may leap over blocked squares, but cannot land on them. The devil wins if the angel is unable to move. The angel wins by surviving indefinitely.

The angel problem is: can an angel with high enough power win?

There must exist a winning strategy for one of the players. If the devil can force a win then it can do so in a finite number of moves. If the devil cannot force a win then there is always an action that the angel can take to avoid losing and a winning strategy for it is always to pick such a move. More abstractly, the "pay-off set" (i.e., the set of all plays in which the angel wins) is a closed set (in the natural topology on the set of all plays), and it is known that such games are determined. Of course, for any infinite game, if player 2 doesn't have a winning strategy, player 1 can always pick a move that leads to a position where player 2 doesn't have a winning strategy, but in some games, simply playing forever doesn't confer a win to player 1, and that's why undetermined games may exist.

Conway offered a reward for a general solution to this problem ($100 for a winning strategy for an angel of sufficiently high power, and $1000 for a proof that the devil can win irrespective of the angel's power). Progress was made first in higher dimensions. In late 2006, the original problem was solved when independent proofs appeared, showing that an angel can win. Bowditch proved that a 4-angel (that is, an angel with power k=4) can win and Máthé and Kloster gave proofs that a 2-angel can win. At this stage, it has not been confirmed by Conway who is to be the recipient of his prize offer, or whether each published and subsequent solution will also earn $100 US.

🔗 Plants

Lithops is a genus of succulent plants in the ice plant family, Aizoaceae. Members of the genus are native to southern Africa. The name is derived from the Ancient Greek words λίθος (líthos), meaning "stone," and ὄψ (óps), meaning "face," referring to the stone-like appearance of the plants. They avoid being eaten by blending in with surrounding rocks and are often known as pebble plants or living stones. The formation of the name from the Ancient Greek "-ops" means that even a single plant is called a Lithops.

🔗 Mathematics 🔗 Philosophy 🔗 Philosophy/Logic 🔗 Philosophy/Epistemology

In the philosophy of mathematics, intuitionism, or neointuitionism (opposed to preintuitionism), is an approach where mathematics is considered to be purely the result of the constructive mental activity of humans rather than the discovery of fundamental principles claimed to exist in an objective reality. That is, logic and mathematics are not considered analytic activities wherein deep properties of objective reality are revealed and applied, but are instead considered the application of internally consistent methods used to realize more complex mental constructs, regardless of their possible independent existence in an objective reality.

🔗 California 🔗 Companies 🔗 Technology 🔗 Private Equity 🔗 California/San Francisco Bay Area

Y Combinator is an American seed accelerator launched in March 2005 and has been used to launch over 2,000 companies including Stripe, Airbnb, Cruise Automation, DoorDash, Coinbase, Instacart, and Dropbox. The combined valuation of the top YC companies was over $155 billion as of October, 2019.