Teach the "what" before the "why"
Start specific and concrete, then move to the general and abstract
Concrete before abstract
Most explanations fail because they start in the wrong place. They begin with abstraction – with general rules, definitions, or theories – before giving the learner something concrete to latch onto.
One of the simplest ways to improve an explanation is to reverse this order. Start with a specific scenario the reader can picture. Then, once that’s sunk in, move to the general idea.
Take the concept of supply and demand. A standard explanation might go like this:
Supply and demand describe the relationship between the availability of goods and the price consumers are willing to pay. As supply decreases and demand remains high, prices rise; as supply increases and demand remains low, prices fall.
The logic is sound, but there’s no image. It asks the learner to juggle definitions before they’ve seen what those definitions refer to. It’s abstract.
Now try the following:
Imagine you’re trying to buy a ticket to a sold-out concert. Lots of people want tickets and there aren’t many left. That means resellers can charge way more than the original price. In other words, demand is greater than supply, and that pushes up prices.
Now imagine the same concert, but there are thousands of empty seats. Ticket prices drop to fill the seats. That’s because supply is greater than demand.
Once you’ve seen the specific scenario of the concert, you can understand how the rule applies more generally. Supply and demand now feel like useful labels for something you already understand.
The same principle applies in scientific subjects. I typed “explain photosynthesis” into ChatGPT, and here’s what I got:
Photosynthesis is the process plants, algae, and some bacteria use to turn light energy into chemical energy stored in sugars. It happens mainly in the chloroplasts of plant cells.
It’s accurate, but it’s abstract. I can’t picture the phrase “turn light energy into chemical energy stored in sugars”. That makes the explanation difficult to follow unless you already know what’s going on.
Now consider this version:
Leave a plant in the dark, it dies. In the sun, it thrives. Why?
Because plants need light to make food.
Here’s how:
– Sunlight shines on the leaves
– Water (from roots) and carbon dioxide (from air) mix in the leaves.
– Powered by sunlight, this mix turns into glucose (food) and oxygen (released into the air).
That’s photosynthesis – plants making food from light, carbon dioxide, and water.
The rewrite is rooted in a concrete example: a dying plant. Then the more abstract idea of photosynthesis can click into place.
What before why
This illustrates an important principle of explanation structure: what before why.
The first version loses most readers before they’ve started. It jumps too quickly to the why – “to turn light energy into chemical energy stored in sugars” – without giving us a concrete what to attach it to. The rewrite starts with an observable what – a dying plant.
Similarly, the supply and demand explanation works better when you first give the reader a what – the sold-out concert – before explaining why prices behave the way they do – due to the laws of supply and demand.
When we learn something new, we need to fit it into the map of knowledge we already have in our minds. Start with the dying plant, or the sold-out concert. Then we can begin to understand how or why they work.
Let’s switch from biology and economics to English. Here’s an explanation of how to use a comma:
A comma is a commonly used punctuation mark that is used to separate two words, phrases or clauses in a sentence. It can also be used in a list to mention different items or articles.
(https://byjus.com/english/comma/)
This is all true. But unless you’ve seen plenty of commas in action, it isn’t particularly helpful.
Instead, look at these two sentences:
Let’s eat, Grandma.
Let’s eat Grandma.
The comma saves Grandma’s life. That’s what it does. Now you understand its importance, you’re better placed to understand when to use it.
The “what before why” approach also works well in maths. First show what a mathematical procedure does, then explain why it works – don’t teach both at the same time. I must thank Kristopher Boulton, from whom I first learnt this tactic!
“What before why” is a handy albeit counterintuitive structural tool. It’s often all too tempting to jump straight to the why. But curiosity needs something concrete to attach to – it doesn’t work in a vacuum.
And that brings us to our next structural tip: whatever you’re explaining, you first need to give your audience a reason to listen. More on that next time…