Can YOU tell which is the strongest? Humans are ‘terrible’ at judging knots – see if you can decipher them

Whether it’s tying your shoelaces or putting on your tie, many of us use buttons every day.

Despite this, research has shown that humans are ‘terrible’ at judging knots.

Scientists from Johns Hopkins University showed participants photos of knots and asked them to identify the strongest one.

Amazingly, they found that most people had difficulty distinguishing a weak knot from a strong one.

“People are terrible at this,” says study co-author Chaz Firestone.

‘Mankind has been using knots for thousands of years. They’re not that complicated; it’s just a string tied in a knot.

“Yet you can show people real photos of knots and ask them for an opinion on how the knot will behave, and they have no idea.”

Can you tell which of these four knots is the strongest? Scroll down for the answer!

The research was led by Sholei Croom, a PhD candidate who wanted to investigate how people perceive knots.

“People make predictions all the time about how the physics of the world will turn out, but something about knots felt counterintuitive to me,” Ms. Croom said.

‘You don’t have to touch a stack of books to judge its stability.

‘You don’t have to feel a bowling ball to guess how many pins it will knock down.

“But knots seem to strain our judgment mechanisms in interesting ways.”

The team enlisted 50 participants, who were shown four knots and asked to choose which was the strongest.

Physically, all four knots were similar, but the difference was in their strength: the force required to untie them.

For example, the reef knot is the strongest knot in existence, while the mourning knot can be unraveled with a gentle push.

To simplify matters, the researchers then showed participants pictures of just two knots and asked them to point to the strongest one.

The results showed that participants consistently failed to correctly identify the strongest knot.

To simplify matters, the researchers then showed participants pictures of just two knots and asked them to point to the strongest one.

Again, they couldn’t.

Finally, they showed participants videos of each knot, slowly rotating the knots so they could get a good view from every angle.

Once again the participants failed to get the strongest knot.

“We tried to give people in the experiment the best chance we could, including showing them videos of the knots turning, and that didn’t help at all – people’s reactions were even more all over the place,” Ms Croom said.

‘The human psychological system simply fails to obtain physical knowledge from the properties of the knot.’

Although the reason for the findings remains unclear, the researchers suggest that objects that are not stiff, such as string or string, are more difficult for people to reason about.

“We’re just not able to get a clear picture of the internal structure of a knot by looking at it,” Ms Croom added.

‘It’s a great case study of how many open questions remain in our ability to reason about the environment.’

The answers

1. Node A is the strongest

2. The reef knot (top) is significantly stronger than the grief knot (bottom)