How a dishwasher works

A dishwasher is the most mysterious domestic appliance. You shut the door, turn it on, hear the sounds of sloshing water, and the dishes appear clean. I had assumed that it was something like a clothes washing machine in that it filled the container with water and then churned it around. But I noticed that our new dishwasher seemed to go into the sloshing sound mode pretty quickly, long before there would be time to fill the volume. So I was glad to come across this video where someone had placed a camera inside the dishwasher to reveal its secrets.
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The conjunction fallacy

Rob Brooks asks you to take a pop quiz:

When Jack was young, he began inflicting harm on animals. It started with just pulling the wings off flies, but eventually progressed to torturing squirrels and stray cats in his neighbourhood.

As an adult, Jack found that he did not get much thrill from harming animals, so he began hurting people instead. He has killed 5 homeless people that he abducted from poor neighbourhoods in his home city. Their dismembered bodies are currently buried in his basement.

Now, knowing what I have just told you about Jack, is it more probable that Jack is: A) A teacher. Or B) A teacher who does not believe in God?

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Co-ed lab rats

It is quite odd how some things that should be obvious are not so purely because tradition has deadened our sensibility. For example, it has long been standard practice for medical research on animals to use only male specimens since it was argued that the presence of female hormones would add another uncontrollable variable in the testing. This seemed reasonable enough that it was uncontroversial until people started finding that when the resulting medicines were used on women, unexpected things happened. The National Institutes of Health now demands that all testing be done on both males and females, something that seems glaringly obvious now.
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Studying dog emotions

Owners of dogs don’t need much convincing to believe that their pets can sense their moods and respond accordingly. But now scientists have done something quite remarkable and that is to train dogs to lie so still that their brains can be studied in an MRI machine and their response to emotionally loaded sounds analyzed and compared to those of human subjects.
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Authenticating ancient documents

Modern scholarly techniques are used to detect which ancient documents are genuine and which are forgeries. In 2012 there reports of the discovery of a piece of papyrus that seemed to suggest that Jesus had been married. The document had been given by an anonymous person to a Harvard scholar who proclaimed it to be genuine. Needless to say, this caused a huge fuss and scholars pored over it and the weight of their opinions went from genuine to forgery, back to genuine, and now back to forgery again.
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How to cut airplane boarding times in half

When boarding airplanes, different airlines have different policies. The most common policy adopted by airlines is to board passengers by seat rows starting from the back. This makes a kind of intuitive sense. A few airlines have some kind of zone system. About three years ago, a physicist studied the issue using Monte Carlo simulations came up with a plan that can cut boarding times by half.
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