There is a viral YouTube video with over 16 million views
that dramatically demonstrates that a young orangutan can be fooled by a magic
trick. Watch it before you read any further.
Now that you've watched – the orangutan clearly
understands that the fruit is in the cup; it's been watching very carefully.
The cup is capped, briefly goes out of sight and comes back with the cap still
on it. You can almost feel the orangutan's puzzlement when the cover is removed
and the cup is shown to be empty. And then there is an almost human response,
as the orangutan realizes the impossibility of what it's seen and roles on the
ground in laughter.
The developmental psychologist Jean Piaget is famous for
his studies on the development of cognitive abilities in infants and children. Among
other things, Piaget studied the development of object permanence – the
realization that an object still exists, even when it disappears from sight.
The game of "peek-a-boo" you've played with an infant exploits this
idea. For infants less than a certain age you disappear when you cover your
face with your hands. Open your hands and say "peek-a-boo" – you
reappear and are rewarded with smiles and happy squeals and gurgling sounds
from the infant. Wait a few years and the reaction is decidedly different.
One of Piaget's early experiments with object permanence
involved placing a toy under a piece of cloth in front of an infant. Very young
infants fail to search for the toy, but, at about 9 months, the infant will
pick up the cloth, revealing the toy. At that age the child has realized that
objects still exist, even when out of sight. Piaget extended this experiment by
using two pieces of cloth. In full view of the child he hid the toy under the
first cloth. Then, still in full view, he removed the toy from under the first
cloth and moved it under the second cloth. A young infant responds by lifting
the first cloth; only older infants will lift the second cloth.
I first read about Piaget's experiments and theories of
cognitive development when my daughter was around one and a half to two years
old. I was curious about her developmental stage so I conducted the two cloth test
described above. Then I sat back and watched. Was my daughter going to be a
genius for her age or an ordinary child? She hesitated, seemed to collect her
thoughts, then leaned forward and, using both hands, picked up both cloths
simultaneously!
Object permanence is useful for not only humans, but
animals as well. Suppose a squirrel is walking in the woods and sees a bear or
other predator ahead. The predator moves out of sight, behind a bush. Without
the knowledge that objects can still exist even if not seen the squirrel would
keep on walking in the same direction, with disastrous consequences.
Not only will the sense of object permanence reduce the
chance that you'll fall victim to a large predator it will enable you to enjoy
a performance of magic as much as an orangutan. Unfortunately most people have
never had the pleasure of seeing a live performance of close-up magic in which
things appear, change and/or disappear right under their noses. Many of these
take advantage of the object permanence bias that we all learned as infants. As
examples, I encourage you to view these videos of this beautiful card trick, Slydini fooling Dick Cavett with coins
and this trick with a single cup and ball. You probably won't roll on
the floor laughing like an orangutan, but I bet you'll be smiling.
