Post hoc ergo propter hoc

From Wikipedia

Post hoc ergo propter hoc (Latin: “after this, therefore because of this”) is a logical fallacy (of the questionable cause variety) that states “Since event Y followed event X, event Y must have been caused by event X.” It is often shortened to simply post hoc fallacy. It is subtly different from the fallacy cum hoc ergo propter hoc (“with this, therefore because of this”), in which two things or events occur simultaneously or the chronological ordering is insignificant or unknown. Post hoc is a particularly tempting error because temporal sequence appears to be integral to causality. The fallacy lies in coming to a conclusion based solely on the order of events, rather than taking into account other factors that might rule out the connection.

he following is a simple example:

The rooster crows immediately before sunrise;
therefore the rooster causes the sun to rise.


The form of the post hoc fallacy can be expressed as follows:

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Einstein’s Riddle

 Can You Solve Einstein’s Riddle?

Taken from

on September 22, 2016

The following riddle is claimed to have been written by Einstein as a boy. It’s also sometimes attributed to Lewis Carrol, although there’s no evidence that either of them actually wrote it. Either way, it’s fiendishly clever and is popularly called “Einstein’s riddle”. It’s rumored that only 2% of the world can solve it.

See if you can figure it out:

There are five houses in five different colors in a row. In each house lives a person with a different nationality. The five owners drink a certain type of beverage, smoke a certain brand of cigar and keep a certain pet. No owners have the same pet, smoke the same brand of cigar, or drink the same beverage. Other facts:

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From Wikipedia, the free encyclopedia

August 10, 2016


Galileo Galilei (Italian pronunciation: [ɡaliˈlɛːo ɡaliˈlɛi]; 15 February 1564 – 8 January 1642) was an Italian astronomer, physicist, engineer, philosopher, and mathematician who played a major role in the scientific revolution of the seventeenth century. He has been called the “father of observational astronomy”, the “father of modern physics”, and the “father of science”. His contributions to observational astronomy include the telescopic confirmation of the phases of Venus, the discovery of the four largest satellites of Jupiter (named the Galilean moons in his honour), and the observation and analysis of sunspots. Galileo also worked in applied science and technology, inventing an improved military compass and other instruments.

Galileo’s championing of heliocentrism and Copernicanism was controversial during his lifetime, when most subscribed to either geocentrism or the Tychonic system. He met with opposition from astronomers, who doubted heliocentrism because of the absence of an observed stellar parallex. The matter was investigated by the Roman Inquisition in 1615, which concluded that heliocentrism was “foolish and absurd in philosophy, and formally heretical since it explicitly contradicts in many places the sense of Holy Scripture. Galileo later defended his views in Dialogue Concerning the Two Chief World Systems, which appeared to attack Pope Urban VIII and thus alienated him and the Jesuits, who had both supported Galileo up until this point.[8] He was tried by the Inquisition, found “vehemently suspect of heresy”, and forced to recant. He spent the rest of his life under house arrest. While under house arrest, he wrote one of his best-known works, Two New Sciences, in which he summarized work he had done some forty years earlier on the two sciences now called kinematics and strength of materials.

Early life and family

Galileo was born in Pisa (then part of the Duchy of Florence), Italy, in 1564, the first of six children of Vincenzo Galilei, a famous lutenist, composer, and music theorist, and Giulia Ammannati. Galileo became an accomplished lutenist himself and would have learned early from his father a scepticism for established authority, the value of well-measured or quantified experimentation, an appreciation for a periodic or musical measure of time or rhythm, as well as the results expected from a combination of mathematics and experiment.

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