It is ingrained in us to think of people in terms of normal. When we see a deviation from this ‘normal’, we label it dysfunctional or different from the norm. But what does ‘normal’ mean?
In his book The End of Average: How We Succeed in a World that Values Sameness, psychologist Todd Rose argues that when it comes to people, normal doesn’t mean diddly-squat.
I’m not normal. You’re not normal. Nobody you know is normal. ‘Normal’ is a myth, and even when we do define what counts as normal, it’s very rare that anyone real fits this description. So, as much as we’re fond of ranking people as better or worse, comparing and measuring them against some given average, the truth is ‘average’ and ‘normal’ do not exist.
This is because of the jaggedness principle, which states: no one is solely ‘normal’ or ‘average’, nor is there anyone who is solely ‘below average’ or ‘above average’. The principle holds that we cannot apply one-dimensional thinking to understand something that is as complex and jagged such as humans. And what is jaggedness? A quality is jagged if it, a) consists of multiple dimensions. And b) these dimensions are weakly related.
Your height is one-dimension, and it can be measured objectively against others’ heights. Your size, however, comprises many dimensions, such as weight, width, height, length of limbs and so on. Thus, human size is jagged.
I’ll simplify that with two stories demonstrating how the jaggedness principle plays out in the real world.
In the late 40s, the US Air Force noticed that many of their pilots were having trouble operating their planes. Their theory was that people had grown in size since the original cockpit design, and it was time to redesign it to fit this new average-sized pilot. Lt Gilbert S. Daniels was handed the task of discovering the average size of a pilot, and, using a tape measure, he got an average range of 10 different body dimensions.
But to Daniels’ surprise, out of 4,063 pilots, not a single airman fit within the average range on all 10 dimensions. One pilot might have a longer than average arm length, but another, shorter than average leg length. Another pilot might have a big chest but small hips. Daniels’ findings were clear: there was no such thing as an average-sized pilot, and by trying to design a cockpit that fit most ‘normal’ sized pilots, they wound up creating a design that fit no one. They did eventually find a solution — adjustable everything; seats, foot pedals, helmet straps, flight suits.
Around the same time, an American gynaecologist measured thousands of young women and calculated an average size using nine dimensions. He then created an alabaster model of a typical young woman, which he viewed as the ideal female size. He named the model “Norma”.
Based on this model, a local newspaper held a Norma Lookalike Competition — the winner would be the woman who best fit Norma’s ideal physique. No woman came close on all nine dimensions; there was no such thing as the averaged-sized “Norma” woman, not in reality, anyway.
And jaggedness isn’t just about size. Almost every human character — talent, intelligence, character and creativity — is jagged. And yet, most schools, workplaces and society continue to believe in this fictional ‘normal’, designing curriculums and institutions for people around an arbitrary fictional standard called ‘the average’.
You’re not normal. Nobody is.