I heard Malcolm Gladwell, author of Outliers and The Tipping Point, speak a few weeks ago. He spoke about linear thinking – the idea that because we know something
is good for us, we assume that more of it must be better. The truth, he said, is far more complicated, and it’s important to understand that many things are only good for us up to a certain point. After that, what we know to be good things become, in our ignorance, bad things.
The reason is that at a certain point, other factors come into play. Rather than thinking that more is always better, straight up like the letter I, it turns out that the letter U, upside down, is a far better way to picture the beneficial effects of some actions.
Where More is Not Better
Take classroom size. Taxpayers have spent 10s or perhaps 100s of billions of dollars to reduce class size. Yet, 300 studies over 25 years do not support the supposition that small class sizes are actually better. What those studies have found is that yes, reducing class sizes to about 30 students does have benefit. That’s the left side of the inverted U-shaped curve. Fewer students, better teaching, more learning.
Then, something interesting happens. There’s little difference in student performance whether a class has 21 students or 29. That’s the flat top of the inverted U. It turns out that within that range, students benefit from what Gladwell calls ‘pure peers’– students with the same learning style and similar IQ. Thus, teaching progresses at a suitable pace, and more students benefit when peers ask questions.
But below 20 students, there is clear evidence for the downward right side of the curve.
Other factors come into play. The likelihood that any one student is very nearly like other students drops. Students feel isolated. They are less willing to take part in discussion. A too-small class with two kids who hate each other is like driving across the country with three kids in the back seat, he says. The truth, teachers told Gladwell, they don’t want less than 20 students in a class.
In fighting crime, when more than two percent of the community is locked, up, crime rates paradoxically rise. The reasons are that criminals are not just individuals, they are part of the community. They are breadwinners, fathers, caregivers. Removing too many of them tears at the fabric of the community. Gangs form. Drug use rises. More crimes happen.
When More is Not Better for You
The question is not how much can we do – linear thinking says more is always better – the right question – the inverted U-shaped curve question is – how much should we do? When have you heard a school board say we don’t need smaller classes? Or a prosecutor say fewer people should be jailed?
For that matter, when was the last time you said to your child: you’re involved in enough activities. You’ve done enough homework. You’ve tried hard enough. You’ve practiced (insert activity here) enough? When have we said that to our spouses? Or to ourselves?
It’s okay. You’ve done enough. Take a break.