Why the ‘Rule of Three’ is such a powerful concept 🤯: Brain STREAM 2️⃣3️⃣

It hasn’t escaped my attention over the last few weeks of how much I have been calling upon the ‘Rule of Three’ within my life:

• I list three things that went well and three things that didn’t go well when journaling
• I have three 'Quarterly Quests' 🧙‍♂️ to work on over the next three months
• I keep a rolling list of three to dos for each of my PhD projects

This is partially to keep things manageable and partially to give an illusion of choice, without it being overwhelming. Three is often touted as the magic number of writing, art and marketing.

But to what extent is keeping things within a boundary of three a human neurocognitive construct versus its potential to be a more widespread ecological phenomenon? After all if ‘three’ is a widespread adaptation to improve cognition and develop more effective ‘life management’, surely we would expect to see triadic systems spread widely across the natural world?

Let’s dive in.

What is the ‘Rule of Three’?

The name kind of says it all, but the Rule of Three relates to the idea that when things exist in threes they are are easier to convey, understand and remember.

The concept was first documented by scholars in Ancient Greece, but despite its historical roots, the scientific evidence behind the 'rule' isn’t super robust. Most of the research relates to the idea that humans are especially adept at recognising patterns and can only process a certain amount of information at any one time.

One important note to remember is that three is the minimum number of data points we need to discern a pattern. Two data points will always lie on a straight line and can be connected, but only a third will decide on the potential for a pattern to exist.

💡 Action Point: Consider this when you make ‘connections’ between notes or ideas; it does not necessarily mean there is a pattern. But have a third and you may be onto something.

Where is it used?

The rule of three forces us to identify the most important and meaningful aspects of what it is we are describing. It is often mentioned as a tactic to use in presentations, marketing and writing generally:

• “Veni, vidi, vici”
• The Three Little Pigs
• Goldilocks and the Three Bears
• Photography and the ‘rule of thirds’
• The UK government's COVID 19 campaigns

Given its effectiveness at conveying information, perhaps we should seek to use the rule of threes more in our scientific writing.

💡 Action Point: Try writing Atomic Essays, similar to what I have been writing in recent months on the socials. They force you to condense information to around 250 words, keeping your points minimal. Can you condense a research paper into three points? Most can be, though it is challenging when you first try.

So why is the 'Rule of Three' so powerful?

In the spirit of this newsletter which aims to look how the concepts we encounter every day relate to what we see in the natural world, I couldn’t help but notice the lack of distinctive ‘threes’ as found in the world around us.

This would seem to contrast with the title of this newsletter.

There are examples of triadic things in nature - e.g. DNA is made of three components, some flowers - but I struggled to think of a widespread pattern that went beyond categorisation into threes as a human construction. After all DNA is a double helix (though three exists apparently) and more flowers are bilaterally symmetrical than trilaterally symmetrical.

If three is a particularly effective means of communication and learning, would we not see more of it in the world around us? Why then:

• Do lungs, brains, mitosis happen to be in twos?
• Are there no three eared/legged/eyed organisms?
• Is there night/day, aboveground/belowground, air/water, roots/shoots?

The eagle-eyed among you will notice these are all physical things; they either are or they aren’t.

Perhaps the magic happens in the transitions between dyads? It is only when I started considering how things interact with other things, that I started to see the triadic component:

• How the two parts of our brain communicate and lungs co-ordinate
• The link between balance and movement for bipedal and quadrupedal organisms
• Transitions between phases; day/twilight/dark where dawn and dusk are times of intense animal activity, or the ocean surface or inter-tidal zone where organisms live across the boundary

Therefore, this got me wondering whether dyadic components are physical and/or functional whereas triadic relationships (and beyond) are relational. This concept does link us back nicely to one of the original reasons why the ‘Rule of Three’ is thought to be particularly effective - patterns.

When we have a pattern, we have a relationship.

If we have two things, they might work with, or against one another - we don’t know without more information. Having a third component that can describe the relationship between the original two is incredibly valuable to be able to interpret the limitations and benefits of the other.

👉 There is Yin and there is Yang and there is the interconnecting relationship between the two.

Here’s another thing to consider; does the rule of three only work when there is a restriction between two dimensions? Could we consider the Rule of Three as the transitional information between one dimension and a second. Two components of information is a connection, but with three we have a direction, a relationship and/or a purpose and therefore a meaning.

Ultimately, relationships allow us to make predictions. They help us to start to figure out whether there is a cause and an effect.

Beyond two dimensions we need more data and the rule breaks down.

In summary, the Rule of Three is an example of 1+1=3. We have two main data points, and the third acts upon the other two to create something much greater than those two alone; it allows us to place, interpret or use the information we are given.

💡 This thinking is immensely powerful when we consider how we can break down incredibly complex ecological - or personal - interactions and relationships into the information we understand most naturally; in threes. Plus, consider how quickly, even simple experiments can get complicated.

Cool stuff, right? 🤯

I’ll see you for more at the same time next week,

Annette 🤗

Do you have thoughts on today’s post? I’d love to know what you think. Where could you apply the Rule of Three?