The human brain reacts differently to lists of different sizes. When we align what we say with what the human brain expects, we are more effective communicators.
In this blog post I’ll explain how you can leverage how the brain reacts to various quantities to make your speaking and writing more effective.
When we write and speak we often use lists of various sizes. I might have 2 reasons I support the new company strategy. I might tell you my three favorite types of fruit. I might have a presentation that describes 4 new features. There is one vegetable that I like more than any other.
The length of the list affects how the audience interprets what I am saying. We can align what we say with what the brain expects to be more effective communicators.
Not aligning with what the human brain expects is like swimming up stream. Given the choice, why would anyone do that?
I’m going to talk about 3 things:
- Part A: Lists of size 2, 3, and “4 or more”
- Part B: Lists of size 1
- Part C: Giving your audience a mental roadmap
Part A: Lists of size 2, 3, and “4 or more”
First let’s talk about lists of size 2, 3 and “4 or more”.
As I said before, when we write and speak we often use lists of various sizes.
- I’m going to discuss 2 car makers: Toyota and GM.
- My 3 favorite bands are: The Beatles, The Rolling Stones, and Led Zeppelin.
- I ate 9 types of fruit last week: apples, oranges, bananas, grapes, pineapples, cherries, watermelons, blueberries, and pomegranates.
The length of the list affects how the audience interprets what I am saying.
Lists of length 2 encourages comparison. When I told you that I’m going to talk about two car makers, your brain naturally starts comparing them. One is Japanese, the other is not. One is doing financially better than the other, etc etc.
If you have two things, you naturally start comparing them. You’re brain can’t help it. If you want to encourage the audience to compare and contrast, have a list of 2 items.
If you want to discourage comparison, don’t have two items! This may require adding a third item as a decoy!
Lists of length 3 are interesting for a different reason. A typical person can hold three things in their mind at once… not much more. If you are going to talk about many things and it is important that the audience hold those three things in their head as you discuss them, make sure that list is 3 or less.
Suppose I’m going to talk about music groups for an hour. In that time I’m going to be switching back and forth, so I need the audience to hold in their head the names of these bands. I better not be talking about more than 3 bands! More than 3 is too much cognitive load. The audience will get confused or bored or worse.
So what about lists of length 4 or more?
Lists of length 4 or more are difficult for the human brain to remember. In fact, if I told you that last week I ate NINE types of fruit: apples, oranges, bananas, grapes, pineapples, cherries, watermelons, blueberries, and pomegranates… I assure you that you won’t remember the list.
What you will remember was that the list was very long. If that was your goal, congrats!
If my point was that I want the audience to remember that I like a lot of variety, listing many fruits will drive that point home. Next week you won’t remember what I liked, but you’ll remember I liked a lot of different things.
If I want the audience to remember exactly what fruits I like, I better make it a shorter list.
If you really really really want people to remember a list longer than 3, the best you can do it to group the items into three categories. People will remember the categories, not the individual items.
Part B: Lists of size 1
Now let’s talk about lists of size 1.
If you really want people to remember something, it better be just one thing. Any added information is a distraction; people might remember the distraction by mistake!
Today I want you all to remember that I like broccoli. Therefore, I’m only going to mention broccoli.
As an engineer, I feel compelled to let you know that there are other vegetables that I like too… but I’m not going to mention them as it would be a distraction.
I want the list to have 1 item on it. …and I’m going to repeat that one-item-list a lot.
I like broccoli. That’s what I want you to remember. In the last month I’ve had broccoli 6 different ways: I had it raw, steamed, sautéed, roasted, blanched, and in a garlic sauce. I love broccoli. I really love broccoli.
Next year when I ask you about this you will remember that I like broccoli because I had the self control to not mention the others that I like.
Right now I feel like I’m being a little dishonest because there are other vegetables that I like, but since I want you to remember broccoli, I’m going to use some self-control and not mention… ohh boy do I want to tell you. Nope, nope nope. Not gonna do it.
If you want the audience to remember something, don’t distract them with things you don’t want them to remember.
Getting people to remember something is like getting children to eat their vegetables: It’s easier if it’s the only thing on their plate.
Part C: Giving your audience a mental roadmap
Ok, now we’re on the third and final part: Giving your audience a mental roadmap.
Tell the audience the quantity, don’t make them count.
Tell the audience the items up front. Don’t make them wait.
By doing these things, you give your audience a mental roadmap of what is to come. As you present the full details, people fill in that roadmap.
Best of all, they are prepared to do one of three things: compare, hold in their head, or memorize.
Surprise endings are good for mystery novels, but not in speaking or writing. Tell people the quantity up front.
Say, “I’m going to tell you about 3 rock bands: The Beatles, The Rolling Stones, and Led Zeppelin” then tell them about each band, in the order you listed them, then conclude by telling your audience that this was your thoughts about The Beatles, The Rolling Stones, and Led Zeppelin.
This is what your grade school teachers meant when they taught you “Tell them what you are going to say, then say it, then tell them what you told them.” You are creating a mental roadmap, filling in the details, then reminding them what you want them to remember.
This has another benefit for long presentations. During long presentations people get bored and tune out. Each time you move on to the next item it is an opportunity to wake up the bored people so they pay attention again. You can do this easily: Pause when you start each item. The silence will wake them.
It also helps to be very clear that the new topic is starting. If they were bored, maybe they’ll like this next topic. “[pause] And now let’s move onto my next point” or “[pause] Now that we’ve learned about The Beatles, let’s talk about Led Zeppelin.”
This pause is called a book-end. By “bookending your topics” you wake up the bored people, and give those that were paying attention a mental break.
I often structure my talks as a “Top 5” or “Top 10” list. This gives people a mental roadmap, it gives bored people many chances to wake up, and it also helps people gauge how much progress I’ve made through the list. Instead of wondering, “Oh god how much longer is this stupid talk going to be?” they’re thinking “Ok, this is point number 8. Maybe number 9 will be more interesting.”
These tricks really work.
That’s why I told you there are 9 types of fruit I ate before I started naming them. I wanted to mentally prepare your brain to hear a long list. If you weren’t prepared, your brain would freak out and worry that I would never stop listing names of fruit.
That’s why I told you I had one favorite vegetable, broccoli, and never mentioned any other vegetable.
That’s why I told you this talk has 3 parts. Because now you know that this blog post is done.
P.S. This article made 6 points but because I presented them as 3, you were more likely to hold them in your head and follow along. By including this point in a P.S. I’ve extended that to 7 points. By going against the rules, I’ve created a contrast that makes this last point stand out. Only break these rules once per talk and do it with purpose!