As I was perusing a recent issue of Science I came across an article that seems to confirm the thesis of Malcolm Gladwell’s latest book Blink. According to Gladwell the human brain is able to make snap judgments that are more accurate than those arrived at through a more systematic weighing of the available options. I started out thinking I would post on this article, but then I decided to Google it to see if someone else had beaten me to the punch. Sure enough, Gareth Cook, a writer for the Boston Globe had gotten there first. His article sums up the Science piece pretty nicely; it’s well worth reading.
I decided to expound on why the brain can make these snap judgments so accurately. I was pondering this very thing the Friday before Presidents’ Weekend as I was trying to get home and back in a hurry during a brief break in the Renaissance Weekend program. Traffic, which is usually fairly tame in Santa Barbara, was brutal. Cars were backed up to a standstill on the 101, the only freeway running through town. I bailed out and took the back way, but soon found that I wasn’t alone. It appeared that everyone else who knew the alternate routes did the same thing. It was a crazed, driving nightmare. Cars were darting out from everywhere, switching lanes suddenly without signaling, honking, jockeying for position at each intersection, and in general seemed to have an animus directed specifically at me. It occurred to me during all this chaos that if Benjamin Franklin or Thomas Jefferson (both smart guys by anyone’s estimation) had been with me, or God forbid, behind the wheel themselves, they would have been terrified. Their Revolutionary War, horse and buggy era brains could not have computed the speeds, closing velocities, turning radiuses, breaking distances or any of the other things we all totally take for granted as we drive in traffic.
As I pondered all this it dawned on me why we can make snap judgments that are so accurate: our brains are really statistical computers.
Let’s take the situation where we’re in a car pulled up to a stop sign at a two way stop. We have to stop but the cars coming from our right and left don’t. As we look both ways for traffic before we cross the intersection and continue on our way we see a car coming from the right, but it’s a several hundred feet from the intersection and we know we can easily make it across without causing the car coming from the right to even slow down. We take a quick look to the left to make sure there is no new traffic coming from that direction, step on the accelerator and cross the intersection in plenty of time to avoid the car closing from the right. This happens hundreds of thousands of times probably each and every hour all across the country. We’ve all done it thousands of times ourselves without giving it a moment’s thought. The stakes are pretty high in this venture because if we happen to be wrong and misjudge the closing speed of the car coming from the right, we could be seriously injured or even killed. But we never are because we easily make it across every time.
How? Think of all the variables involved. We have to estimate the speed of the approaching car and figure how long it’s going to take before it’s on us. We know the acceleration of our own car and have to calculate how quickly we have to cross the intersection to avoid a collision. And we do it all in a split second while listening to the radio and thinking about something else.
How can we do this? We can do it because we’ve been there before. Odds are when we first started driving we would have waited for the car coming from the right to pass before we attempted to cross because we hadn’t seen that situation many times before and weren’t capable of making a reasonable judgment as to how fast the car was closing on us. Every time since that we’ve pulled up to an intersection and seen cars coming from the right or left we have gained experience. If we see a car way to our right and wait for it, we say, I could have made it. And our brain remembers. If we dart out in front of an approaching car that has to hit the brakes to avoid a collision, our brain remembers that, too. After we have confronted many intersections and have witnessed countless cars coming from all directions, our brains learn to compute the approaching speeds and make incredibly accurate go-no go decisions. Where Benjamin Franklin would be paralyzed with fear, we cross the intersection well in front of a three thousand pound chunk of metal hurtling at 45 miles per hour in our direction. And we do it without a second thought. Our confidence level that we’re going to make it is much higher than the 95 percent confidence level used statistically in most studies. We have, in fact, virtually a 100 percent confidence level.
Since over the course of our lives our brains have been programmed by not just approaching cars, but by the totality of all our experiences, it makes sense that we should be able to make fairly sophisticated decisions with just a moment’s thought.
For example, in my own case it took only a glance to let me know I didn’t like Dean Ornish.


  1. I really like your blog and check in faithfully each day to see what you have come up with! Thanks for putting a smile on my face- Wind chill is 20 below zero here in Maine and I need all the smiles I can get!

  2. Honestly, I can not say that I’ve ever spent so much mental energy in the analysis of a simple driving maneuver.
    However, after whistling the double fugue at the end of Beethoven’s 9th symphony and then suddenly arriving at my destination, I often wonder how I did it without having a crash…

  3. I do not understand why, if soybean oil and canola oil contain transfats, this information is not listed on the new nutrition labels which went into effect in January. How can these products list 0% transfats in the nutritional breakdown when the oils used contain transfats. Could you please clarify this for me?

  4. Pure soybean oil doesn’t contain trans fats, only partially hydrogenated soy bean oil. As best I can tell from the literature, about 70 percent of the soybean oil produced ends up being partially hydrogenated. If it is partially hydrogenated, then it must (should) be listed on the labels as a trans fat after Jan. 1, 2006.
    Canola oil is a little different story. Canola oil as it comes from the rapeseed (canola oil is really rapeseed oil, but since ‘rape’ is a highly charged word producers of rapeseed oil call it canola oil) has a strong, extremely unpleasant odor. During the deodorization process a portion of the canola oil undergoes partial hydrogenation, a fact published in a couple of technical oil processing papers. Since the oil isn’t hydrogenated on purpose, but secondarily as a by product of deodorization, canola oil has gotten a pass. MD and I no longer use canola oil for this reason.

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