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Investigates why we get stuck, focusing on mental sets, functional fixedness, and cognitive rigidity.
Why did a group of elite engineers struggle for hours to move a truck stuck under a low bridge, only for a passing child to solve it by saying, 'Why don't you just let some air out of the tires?'
In psychology, functional fixedness is a cognitive bias that limits a person to using an object only in the way it is traditionally used. This concept was famously illustrated by Karl Duncker’s Candle Problem. Participants were given a candle, a box of thumbtacks, and matches, and told to attach the candle to the wall. Most failed because they viewed the box only as a container for the tacks. To solve it, one must see the box as a potential platform. This 'fixity' happens because our brains prioritize efficiency; we categorize objects by their primary function to save mental energy, but this often blinds us to creative 'hacks' in novel situations.
1. Scenario: You need to tighten a loose screw but don't have a screwdriver. 2. The Block: You look around for a tool kit and, finding none, give up. 3. The Solution: You realize a dime or a sturdy butter knife has a thin edge that fits the screw slot. 4. Outcome: By overcoming functional fixedness, you repurposed a coin as a tool.
Quick Check
If you are using a heavy textbook as a doorstop, which cognitive bias have you successfully overcome?
Answer
Functional fixedness.
A mental set is a tendency to approach a problem in one particular way, often because that way has been successful in the past. While helpful for routine tasks, it creates cognitive rigidity when a problem changes. Abraham Luchins demonstrated this with his 'Water Jar' experiments. Participants learned a complex formula to get a specific amount of water: . When later given a much simpler problem that could be solved with , they continued using the long, complex formula. They were 'set' in their ways, proving that past success can sometimes be a barrier to future efficiency.
1. Task: Solve for in a series of equations. 2. Pattern: The first five problems require the quadratic formula: . 3. The Trap: The sixth problem is . 4. Rigid Response: You immediately begin identifying for the quadratic formula. 5. Flexible Response: You recognize , so , saving three minutes of calculation.
Quick Check
True or False: A mental set is always harmful to problem solving.
Answer
False. Mental sets are often helpful for routine problems; they only become 'blocks' when they prevent us from seeing a simpler or necessary new solution.
To combat cognitive rigidity, psychologists suggest several techniques. One is incubation: stepping away from a problem to allow the unconscious mind to work. This often leads to an 'Aha!' moment or insight. Another is divergent thinking, where you deliberately brainstorm multiple uses for a single object. By consciously questioning the 'rules' we assume exist, we can shift from a rigid state to a flexible one. This is essential in high-stakes environments, like NASA's mission control, where engineers must solve life-threatening problems using only the limited, 'fixed' items available on a spacecraft.
1. Problem: Astronauts had square carbon dioxide filters, but the socket in the Lunar Module was round. 2. Constraint: They had no spare parts and limited time before oxygen ran out. 3. Overcoming the Block: Engineers on Earth ignored the 'intended use' of flight manuals, plastic bags, and duct tape. 4. Solution: They built a 'mailbox' adapter using these random items, successfully connecting the square filter to the round hole and saving the crew.
Which researcher is famous for the 'Water Jar' experiment regarding mental sets?
In the 'Candle Problem,' the box of tacks is usually seen as a container. To solve the problem, it must be seen as a support. This shift is an example of overcoming:
Incubation involves actively focusing harder on a problem until the solution appears.
Review Tomorrow
In 24 hours, try to explain the difference between a 'mental set' and 'functional fixedness' to a friend using the 'Water Jar' and 'Candle' examples.
Practice Activity
Try the 'Alternative Uses Task': Pick a common object (like a brick or a paperclip) and list 10 uses for it that are NOT its intended purpose. This builds divergent thinking!