Letters Archive
Why is America called America?
The name America was derived from the Italian explorer Amerigo Vespucci, who discovered new lands and wrote about his experiences.
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Astrolabe and Compass
The invention of the magnetic compass in China around the 11th century was a game-changer, giving sailors a consistent way to determine direction.
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Rules of Debate
Recognizing logical fallacies is just one important aspect of critical thinking, and knowing about them can help you make better, more sound arguments of your own.
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Columbus makes his pitch
Columbus had a big dream - to find a new route to Asia by sailing west across the Atlantic, and his persistence paid off when he finally received approval for his voyage in 1492.
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Habit Formation
Learn how to form good habits using the 3Rs of habit formation: Remember, Repeat, and Reward.
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Running experiments with the Skinner box
The Skinner box was a controlled environment for running experiments, and B.F. Skinner discovered that the timing and frequency of rewards could dramatically affect behavior
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Skinner and his box
This letter introduces B.F. Skinner, an influential psychologist who expanded on Pavlov's ideas about classical conditioning and operant conditioning through his experiments with pigeons and rats in a 'Skinner box.'
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Pavlov's Dogs
Discover how Russian scientist Ivan Pavlov accidentally discovered classical conditioning and its impact on our behaviors and reactions!
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