A little knowledge can be a dangerous thing. Most of us have heard of this admonition, and it applies directly to engineering education. It turns out that people who know just a little about a subject greatly overestimate their understanding and abilities. “The Dunning–Kruger effect is a cognitive bias in which people wrongly overestimate their knowledge or ability in a specific area. This tends to occur because a lack of self-awareness prevents them from accurately assessing their own skills” .
The same website goes on to state: “Those with limited knowledge in a domain suffer a dual burden: Not only do they reach mistaken conclusions and make regrettable errors, but their incompetence robs them of the ability to realize it. The Dunning–Kruger effect results in what’s known as a ‘double curse:’ Not only do people perform poorly, but they are not self-aware enough to judge themselves accurately—and are thus unlikely to learn and grow. The effect isn’t spotted only among incompetent individuals; most people have weak points where the bias can take hold. It also applies to people with a seemingly solid knowledge base: individuals rating as high as the 80th percentile for a skill have still been found to overestimate their ability to some degree. This tendency may occur because gaining a small amount of knowledge in an area about which one was previously ignorant can make people feel as though they’re suddenly virtual experts. Only after continuing to explore a topic do they realize how extensive it is and how much they still have to master.”
Confidence in one’s state of knowledge can be represented graphically as a high peak when just a little knowledge is possessed, followed by the realization that one is not as capable as previously thought, and then a slow return of confidence as more knowledge about the subject is acquired . This is represented in Figure 1.
I don’t know for sure, but I would guess that almost every student of higher education goes through this know-it-all stage as they attain some knowledge in their introductory courses. It seems that engineering undergraduate students do. I was not immune to the know-it-all stage myself. I remember coming home from spring semester at college, just having taken a Strength of Materials course, and finding that my father was building a new shed on our farm. He was using two-by-fours to frame the roof, and he was laying them flat, with the 4 in dimension in the horizontal direction. I, of course, after taking my courses that semester, knew all about the strengths of beams. I knew that the strength of a beam was proportional to bh2, where b was the base measurement, and h was the height measurement. If my father turned the two-by-fours around so that the height would be 4 inches rather than 2 inches, then the strengths of those same boards would be twice what it was with the 4-inch side horizontal (2 × 42 = 32 compared to 4 × 22 = 16), and the beams would be a lot less likely to bend under a snow load. I wondered with a slight amount of smugness why he was using the boards in the way that he was. I proudly told my father about what I had learned in school. He listened, but didn’t say anything that I can recall. He did, however, turn the two-by-fours around. It was only later that I realized that nailing the two-by-fours to the members underneath them is much easier when they are lain flat, with the nails only having to be pounded through 2 inches of wood rather than 4 inches. He was doing the practical thing determined by the effort required to fasten the boards together. I was right, of course, about the strength, but I had not considered the extra work that he would have to do to conform to what I had mentioned to him. There are always practical considerations to any bit of knowledge.
The other side of this issue is that a person at the know-it-all peak is never aware of what he or she doesn’t know. There was a classic cryptic and almost incomprehensible quote by Donald Rumsfeld that states:
“There are known knowns; things that we know we know. We also know there are known unknowns; that is to say, we know there are some things we do not know. But there are also unknown unknowns – the ones we don’t know we don’t know.”
It can be inferred from this quote that there are relevant things about which we know nothing about, and that these things can become harmful just because we are ignorant of them.
The NASA Space Shuttle Challenger disaster in 1986 is a good example of this. As it turns out, there was an O-ring failure in a joint on one of the shuttle solid fuel boosters, leaking hot exhaust gas and causing the shuttle to break apart within 73 seconds after launch. Later, it was determined that the temperature at the lift-off site was too low for the O-ring to seal properly. NASA, however, was anxious to send the shuttle on its mission on schedule after much pre-flight publicity, and so overruled warnings by several contractor engineers that an incident might just occur because of the cold January temperatures in which the shuttle and booster system had stood during the hours before ignition.
The decision by NASA personnel to ignore the warnings was not made without some justification. There had been some incidents of leakage on past shuttle fights, but the relation between leakages and ambient temperature appeared to be random; there was no telling that low temperature was related at all to O-ring failure.
A historical graph of number of flight incidents against launch pad temperature appears in Figure 2. If all that are considered are the cases with O-ring failure, then, indeed, there is no apparent prediction about whether an O-ring incident would or would not occur for the Challenger with an ambient temperature that stood in the range of 36 °F, the coldest temperature of any previous launch. However, if one looks at the data where no incidents had occurred, then all the data points fall at temperatures higher than 65 °F. If that data had been considered by NASA personnel, they might have delayed the launch, and the seven crew members may well be relating space stories to their grandchildren.
Sometimes, the only information of which someone is aware is only a small portion of the information necessary to make wise informed decisions. The Challenger data is an example of this. Someone with a small amount of knowledge about a subject is more likely than someone more knowledgeable to make the mistake of thinking that they have all the information necessary to make important decisions.
Because almost everybody goes through this know-it-all stage, it would be better for engineering students to be made aware of the limitations of their knowledge while still in school rather than after graduation and the beginning of employment. This can be accomplished by providing to the students practical exercises for them to work on in their engineering science and design courses, and these practical exercises should be followed with practical criticisms when warranted , . And, they will, inevitably, be needed. I used to assign practical design problems in my courses on transport process design and electronic design. The students had to either submit transport design reports or to design practical electronic circuits that had to be demonstrated as meeting the specifications of the problem. They learned how to consider and incorporate into their submissions such things as health department requirements, costs of construction, ease of operation, component limitations, sustainability, environmental concerns, and public opinions relevant to the design. Students learned a lot from this approach, and were much better engineering graduates than they would have been had they only had to calculate answers to problems appearing in textbooks. When they later went for job interviews, their interviewers recognized their abilities and they were very successful at landing their favorite employment or graduate education opportunities.
Including practical capstone design courses in the curriculum also help to ground students in practical education. Our students were required to design, build, and test prototypes to meet a list of specifications given to them at the beginning of their capstone design course. I have seen presentations at professional conferences in which were described capstone courses that involved no more than research projects. Whereas students satisfying research projects for their capstone courses may gain some practical knowledge to get them past the know-it-all stage of their education, they still would have a lot to learn if they enter the job market as entry-level engineers. Unfortunately, their first few months of employment might be filled with traumatic moments when they realize that they still have much to learn before they can contribute to the level required of them.
For the same reasons, there is justification for engineering faculty members to be registered Professional Engineers (PEs). Some faculty members chafe under the strong recommendations that they should have passed the PE exam. But, there is some level of professional practicality required to pass the exam, and those who have met this level of accomplishment are at least incrementally better at critiquing engineering undergraduate student submissions than are those with no such experience.
Similarly, adjunct faculty members who have their main employment elsewhere, can be valuable for imparting practical knowledge to their students. I have fond memories of the few adjunct faculty members who were part of my undergraduate education. It is also mostly true that older faculty members can bring valuable experiences to their classroom instruction, and help to make students realize the limitations of the small bit of information that they posses about a subject.
Engineering Practice is not just about “plug and chug” calculation and modeling. A practical design of a product or process involves a lot more than the numerical specifications. There are creative and integrative processes that contribute to the final design, processes that require a more complete education than that retained by the overconfidence of a know-it-all.
- R. Burlow, “Beekeepers and the Dunning-Kruger effect: Unskilled and unaware,’’ Amer. Bee J., vol. 161, no. 4, pp. 381–383, Apr. 2021.
- A. T. Johnson, “Allowing them to fail,’’ BMES Bull., vol. 33, no. 2, p. 1, 2009.
- A. T. Johnson, “Collateral learning,’’ IEEE Pulse, vol. 11, no. 4, pp. 37–43, Jul./Aug. 2020. [Online]. Available: https://www.embs.org/pulse/articles/collateral-learning, doi: 10.1109/MPULS.2020.3008452.
- J. Kruger and D. Dunning, “Unskilled and unaware of it: How difficulties in recognizing one’s own incompetence lead to inflated self assessments,’’ J. Personality Soc. Psychol., vol. 77, no. 6, pp. 1121–1134, Jun. 2009.
- Psychology Today.com. (2021). Dunning-Kruger Effect. Accessed: May 7, 2021. [Online]. Available: https://www.psychologytoday.com/us/basics/dunning-kruger-effect