Figure and Ground

If you’ve taken introductory psychology you know Rubin’s vase, which illustrates the principle of figure and ground: In the image on the left you can see two faces, or you can see a vase, but you can’t see both simultaneously.

A number of people have noticed the same thing in Canada’s modern flag, adopted in 1965 (below). Is this a symbol of Canada’s proud natural heritage or of two people bickering?

And what does that say about Canada?

Pull Over

Americans measure distance in football fields and stones’ throws.

Finns measure it in poronkusema (literally, “passing of water of reindeer”). One poronkusema is the distance a reindeer can pull a sleigh between stops to urinate. It’s 8-10 kilometers, or about five miles.

Need a velocity measure? Poronkusemaa kuukaudessa (poronkusemas per month) is about 0.0289252 meters per second, or 40 feet per hour. Evidently things don’t move fast in Finland.

“The Fuels of the Future”

“With the prospect of coal becoming as rare as the dodo itself, the world, we are told by scientists, may still regard with complacency the failure of our ordinary carbon supply. The natural gases and oils of the world will provide the human race with combustible material for untold ages — such at least is the opinion of those who are best informed on the subject.”

Glasgow Herald, quoted in Scientific American Supplement No. 717, Sept. 28, 1889


When he received the first duck-billed platypus from Captain John Hunter in Australia, naturalist George Shaw thought it was a hoax. “Impossible not to entertain some doubts as to the genuine nature of the animal, and to surmise that there might have been practised some arts of deception in its structure,” he wrote in the journal Naturalist’s Miscellany.

Surgeon John Knox agreed: “Aware of the monstrous impostures which the artful Chinese had so frequently practised on European adventurers … the scientific felt inclined to class this rare production of nature with eastern mermaids and other works of art.”

“Quake Hairs”

From a Scientific American account of a Thai earthquake on May 13, 1848:

During the shock, there spontaneously came out of the ground a species of human hairs in almost every place — in the bazaars, in the roads, in the fields, and the most solid places. These hairs, which are pretty long, stand upright and adhere strongly to the ground. When they are burned, they twist like human hairs and have a burned smell which makes it to be believed that they are really hairs; they all appeared in the twinkling of an eye during the earthquake. The river of Chantibun was all rippling, and bubbles rose to the surface, so that the water was quite white. It is thought that these hairs may have been produced by electricity.

Similar “hairs” have been reported after other Asian earthquakes. Some have been identified as fibers from the hemp palm Chamaerops fortunei, a native tree. Others remain unexplained.

The Flynn Effect

Are we getting smarter? IQ scores around the world have been going up by about three IQ points per decade.

Suggested reasons include improved nutrition, smaller families, better education, and the stimulating modern environment, but no one really knows what’s causing it.

It’s called the Flynn effect, after New Zealand political scientist who discovered it.