My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original posts. This week in my From the Archives series: see something where nothing exists? It's okay: you're in good company.

Everyone plays the game as kids—the one where you look for objects in clouds, right? Even the least-imaginative kids could at least see sheep. Well, it turns out there's a name for it, and it's actually pretty important.

Whoa

It's called pareidolia. Broadly speaking, this is the brain's ability to perceive a familiar pattern in a stimulus where none actually exists. Other examples: mountainsides that resemble faces and trees that look like people.

People aren't the only entities that experience pareidolia. Computers do it, too. Google has a program called DeepDream that specifically sets out to exploit this, and it produces some really, really weird results. (DeepDream especially sees a lot of dogs.)

Pareidolia is fairly important in science, and it causes a lot of problems in archeology and paleontology. Amateurs are constantly picking up rocks they mistakenly think are arrowheads, dinosaur eggs, or bones. This happens so much that there's a specific name for rocks like this: mimetoliths. This also includes larger rocks, like the mountainsides that look like faces.

Yeah, well.

The most famous applied use of pareidolia is the Rorschach inkblot test, which is supposed to give insight into a person's mental state. A fairly successful tool, we’ve used the Rorschach continually since the early 20th century—fairly astonishing, since psychology has thrown away so much from that time period.

If you're familiar with the tabloid-fodder “Jesus appears on toast” articles, you've stumbled on another example of pareidolia. (And we know a woman who saves pieces of firewood because of, well, all those faces she sees in them. Apparently, they make for good company. We hope she has enough non-faced wood to keep warm this winter.)

It also sees extensive use in art, which is unsurprising. Many optical illusions (like the famous one that could either be a lamp or two faces) are good examples. Leonardo da Vinci wrote about pareidolia as a tool in art. Pareidolia is one of the main reasons cartoons work so well, making it easy for us to assign complex emotions to simple line drawings of people.

Pareidolia isn't good or bad—just reflects an aspect of how our brains interpret the world—but can also lead you astray. This phenomenon is also probably one of the coolest oddities involved in discovering how our brains work.

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original posts. This week in my From the Archives series: alternative search engines. WolframAlpha'ing, anyone?

Q: What is the average weight of a panda?

A: 170-290 lbs.

Searching for Engines

There are a lot of different search engines out there, but most people never feel the need to go past Google. For the most part, I'm with them. I have discovered a few specialty search engines that I visit on a regular basis. Most of these are simply engines that search inside a specific website, usually Wikipedia. There are a couple exceptions, though. The biggest one is called WolframAlpha.

Q: How many people have the given name McCoy?

A: 1649 estimated to still be alive in the United States.

Strictly speaking, WolframAlpha isn't a search engine at all. It's a computational knowledge engine. Its creator, Stephen Wolfram, designed the engine to answer factual questions by using its curated internal database of information. This is a very different function than search engines, which provide a list of documents or web pages that might contain the answer.

Q: Motorcycle traffic in Germany?

A: 11.1 billion vehicle miles per year.

WolframAlpha can perform arithmetic, trigonometry, algebra, and numerous other mathematical functions. It contains population estimates from around the globe. It records weather data from the past in the database. And so this computational knowledge engine can use all of this information, along with its countless volumes of other information, to calculate the answers to a huge number of questions.

Q: Melting point of teflon?

A: 327 degrees Celsius. (620.6 degrees Fahrenheit)

Not to say that Wolfram Alpha is perfect. Its databases don't contain anywhere close to even a significant percentage of human knowledge. It doesn't know the average speed of a turtle, for instance, so you couldn't use it to figure out how long it would take one to cross the United States.

My own computational knowledge engine.

A fun Twitter account I ran into the other day is dedicated entirely to sharing odd questions that Wolfram Alpha can't answer. My personal favorites:

• “Hectares of cotton crops needed to make a superhero cape for every land mammal.”
• “Total work done against gravity to make a cupcake rise while baking it, in calories?”
• “Most common English misspelling that changes the word's Scrabble score by more than 4?”

And knowledge crawls onward…

Q: Anchorage, Alaska weather on 7/7/07?

A: Overcast, 54 to 61 degrees Fahrenheit, wind 0 to 7 mph.

Q: Most frequently erupting volcano?

A: Stromboli, in Italy.

Q: 20 gallons of gloss paint?

A: 14,000 square feet, assuming it has a spreading capacity of 690 square feet per gallon.

Q: How long did the Paleoproterozoic Era last?

A: 900 million years.

Q: x+y=10, x-y=4

A: x=7, y=3

Q: What's the temperature of the solar wind?

A: 31,000 Kelvin.