(via NewScientist)
I am just a poor boy, though my story’s seldom told
I have guessed that the resistance,
of a smaller box of equal weight is heavier.
All lies and jest!
Still a man lifts what he wants to lift and disregards the rest.
A study done at Dalhousie University in Canada says that someone who lifts two boxes of equal weight but different size, will estimate that the smaller box is heavier. They will do this even after examining the contents of the box. What’s even weirder is that a lifter will equalize the amount of force they use to lift each box even while maintaining that one is heavier than the other.
Why do we make this mistake? Well, the researchers were able to reverse a volunteer’s estimations through training so that they would think a larger box was heavier than a smaller box of equal weight. This suggests that our estimations are based on previous experiences.
Makes sense, right? Think back to a time (perhaps as a child) when you struggled to lift a large pitcher of iced tea that your mom made for a big dinner. Next time you went to lift that pitcher out of the fridge, you probably put a little more muscle into it to compensate for what you experienced the first time. And what happens the next day when you decide a little more iced tea might be nice? You grab the pitcher with confidence and smash it into the shelf above. Why? Because your brain stored a short-cut for how to approach that pitcher.
Well, your brain does the same thing with the boxes. Smaller objects tend to be lighter than big ones. So, when faced with two boxes, you put a little more oomph into the larger box and a little less into the smaller which makes the smaller one feel a little heavier since it weighed more than you expected.
The researchers conclude that our sensorimotor system (how our muscles move) and our perceptual system (what we experience with our senses) estimate weight differently. Our muscles act as though they are lifting boxes of equal weight while we consciously think the boxes are weighted differently.
This also seems to show that the way we react to lifting a box has little to do with our reason and more to do with some automated calculations performed by our brains.
PS – My apologies to Paul Simon.
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