Why do experienced people mistake expertise for common sense?
What looks obvious to an expert may be invisible to a novice. In schools, it’s just common sense can dismiss the very knowledge someone has not yet had the opportunity to build.
A casual, social slur
The ‘curse of expertise’ is the tendency for experienced people to forget how much knowledge novices need before something appears obvious. Working as a senior leader in a large secondary school in central London, I remember having a fleeting conversation with a younger member of staff. They had a problem to resolve. I cannot remember the topic, the context or even the precise details, but I do remember my reply.
“It’s just common sense.”
I had no idea I had offended them.
At the time, I probably thought I was being helpful, perhaps even efficient. Twelve years later, I still remember that small moment because it taught me something important: what appears to be “common sense” to an experienced person may be anything but clear to someone else.
That phrase, “It’s just common sense”, is one of those casual social slurs we should probably use less often. Not because people are fragile, but because the phrase quietly implies a knowledge deficit in someone else’s thinking, when what may really be missing is prior knowledge. Replying to someone with, “It’s just common sense”, implies:
- You should already know this.
- You should have already worked this out for yourself!
- This is obvious. Why can’t you see it?
But it is not common sense at all. It is knowledge.
Established knowledge feels obvious to the expert
Over the last 15 years, I have spent more time trying to understand neuroscience, neuropsychology and cognitive science: how the brain learns, how knowledge accumulates, and how memory supports decision-making.
In education, I have also been pulled into countless debates about knowledge versus skills. It is a false opposition. Skills do not float around in the air.
Creativity, problem-solving, questioning, evaluation, leadership and judgement – they all depend on established knowledge. Creativity is not the absence of knowledge. It is a knowledge domain in its own right. Expertise is built.
It is practised, revisited, refined, forgotten, retrieved, corrected and strengthened. Over time, knowledge becomes automated. The expert no longer has to consciously think through every tiny decision because much of the thinking has moved into long-term memory.
That is why expertise can look effortless, and be assumed as ‘common sense.’
A skilled teacher can scan a classroom and notice a child drifting before anyone else has seen it. A headteacher can hear a sentence in a meeting and detect a safeguarding risk. An experienced chef can taste a sauce and know exactly what is missing. A mechanic can hear an engine and suspect the fault.
I used to experience this in my own design and technology classroom. With 30 students banging hammers, machines on, and conversations happening, I could hear a saw ‘ping’ and break in two from the other side of the classroom. To the expert, this can feel like instinct. But it is not magic.
It is memory. It is pattern recognition. It is knowledge, deeply encoded.
The novice sees a different problem
Now place a novice in the same situation.
Imagine you know very little about quantum physics, assessment design, school timetabling, safeguarding thresholds, curriculum sequencing or behaviour systems. Someone gives you a problem to fix and says, “Well, it’s just common sense.” Where do you start?
You may not know what matters. You may not know what to ignore. You don’t know the relevant vocabulary, or the relevant rules that apply. You may not even know what a good answer looks like. And this is the curse of expertise. The more we know, the harder it can become to remember what it felt like not to know.
In cognitive science, we might talk about schema: the mental structures that help us organise knowledge. I like to describe this as a spiderweb. If I were a spider, what would I do first? How does the spiderweb form over time, and what happens when various anchor points break? Experts have richer, better-connected schema. They can hold more relevant information in mind because much of the background thinking has become automatic.
Novices cannot do this yet.
So, when an expert says, “It’s just common sense”, what they may really mean is, “I have seen this before, and solved this type of problem many times.” That is not common sense. That is expertise.
The tomato ketchup problem
Let me use another example. I am an expert in tomato ketchup.
Ask me anything about it. I can recall facts, concepts, rules and processes. I know the ingredients, the history, the texture, the balance of sweetness and acidity, the role of vinegar, sugar, tomato solids, seasoning and preservation.
Now, what happens if you ask me to make tomato ketchup?
Because I already have a strong background knowledge, you may now teach me how to adapt it. Perhaps we want a spicy version. The teacher introduces chilli into the learning process, or perhaps we want a barbecue flavour. The teacher discusses smoke, molasses, brown sugar, soy sauce, cider vinegar and heat. To the expert, all of this appears obvious. But to the novice, this is not obvious at all. It is a complex web of knowledge: ingredients, ratios, taste, chemistry, process, timing and judgement.
However, I do NOT know anything about ‘scoville‘, the measurement of spicy heat in chilli peppers. I might use a habanero chilli instead of mild chipotle pepper, and completely ruin the recipe! But the good news is that knowledge is built on the foundations of information you already have stored. The message? The novice sees complexity and possibly makes the wrong decisions because the knowledge has not yet been organised.
Why knowledge matters in schools
The point is not tomato ketchup. The point is knowledge transfer. We can only adapt, improvise or make good judgements when enough relevant knowledge is already organised in memory.
This has significant implications for teaching and school leadership, particularly when public debate caricatures ‘teaching knowledge’ as a direct transmission of facts. That criticism often misunderstands how learning works. It’s another social slur, driven by the media, which lacks expertise in how learning actually happens.
Teaching children how to learn, as well as the selection of knowledge chosen in our curriculum, is critical. However, in our classrooms, despite being an expert in our subjects, we, as teachers, can fall into the trap of ‘common sense’, often unintentionally.
“Just show your working out”, the teacher says, or “Just use your initiative.”
These assumptions often hide a sequence of knowledge, modelling, practice, feedback and confidence that a pupil does not yet possess. School leaders can make the same mistake with staff, too. As I described in my opening paragraph, I did it too, but I won’t do it again. We can quite easily reply to someone in a conversation:
“Just follow the behaviour policy.”
None of these things are simple when you are new, don’t yet have the knowledge, or are under-supported or working in a complex environment. Experts should always remember this. We cannot know or assume everything.
Cognitive apprenticeship
One useful idea for teachers to consider is cognitive apprenticeship – just as important as the research on cognitive load theory. In summary, this research suggests making expert thinking visible to the novice.
Rather than saying, “Use your common sense”, the expert models what they notice, what they ignore, what they prioritise and why. For example, “I noticed the pupil had stopped writing before they became disruptive. I chose to intervene early because this usually prevents escalation.”
Instead of assuming, “It’s just common sense”, we should ask ourselves, “What knowledge is missing here?” That question changes everything.
The next time we are tempted to say, “It’s just common sense,” perhaps we should pause and ask: What expert knowledge have I forgotten that I once had to learn?
- Collins, A., Brown, J. S., & Newman, S. E. (1989). Cognitive apprenticeship.
- Sweller, J. (1988). Cognitive load during problem solving: Effects on learning.
- Willingham, D. T. (2009). Why Don’t Students Like School?
- Chi, M. T. H., Glaser, R., & Farr, M. J. (1988). The Nature of Expertise.
- Deans for Impact. (2015). The Science of Learning.
