THOUGHT EXPERIMENT: Solve this problem: Jack is looking at Anne, but Anne is looking at George. Jack is married, but George is not. Is a married person looking at an unmarried person?

A) Yes.

B) No.

C) Cannot be determined.

The problem is taken from the work of Hector Levesque, a computer scientist at the University of Toronto. More than 80 percent of people choose C. But the correct answer is A. Anne is the only person whose marital status is unknown. You need to consider both possibilities, either married and unmarried, to determine whether you have enough information to draw a conclusion. If Anne is married, the answer is A: she would be the married person who is looking at an unmarried person (George). If Anne is not married, the answer is still A: in this case, Jack is the married person, and he is looking at Anne, the unmarried person.

To solve this you have to approach the problem on its own terms and think inclusively which means to consider all possibilities. Most people are educated to think exclusively which means to reduce possibilities. This kind of thinking also requires less effort. The fact that the problem does not reveal whether Anne is or is not married suggests to people that they do not have enough information, and they give the easiest inference (C).  This is an example of how easily we robotically default to the mental processes that require the least effort.

We are mentally lazy. Our education has conditioned our brains to circumvent deliberative and creative thinking wherever possible through rote memorization and robotic learning of formulas and principles. We have not been taught how to think for ourselves, we have been taught what to think based on what past thinkers thought. We are taught to think reproductively, not productively. We have been trained to seek out the neural path of least resistance, searching out responses that have worked in the past, rather than approach a problem on its own terms. This kind of thinking is dehumanizing and naturalizes intellectual laziness which promotes an impulse toward doing whatever is easiest or doing nothing at all.

Here is a general law of nature: When organisms no longer use something they have — no matter what it is, eyes, brilliant colors, wings, or even brains — that something rapidly evolves  and becomes  lost. Consider flight in birds. Birds typically live longer than mammals of the same size, in part because they can escape from predators more easily. However, flight can take a lot of energy, and it keeps you small. Thus, if there aren’t any predators — as on remote islands — the birds become lazy and flightlessness quickly evolves.

The soil bacterium Myxococcus xanthus normally has an elaborate social life; bacteria hunt together and cooperate to build spores. But if you keep the bacteria in bottles of liquid, you can put an end to their social lives by continually shaking the bottles and interrupting their social discourse. After generations of such treatment, the bacteria become anti-social. They can’t work together anymore and die off.

Any new set of conditions occurring to an animal which render its food and safety very easily attained, seem to lead as a rule to degeneration. Suppose you have a vial full of fruit flies. You assign a mate to each fly at random — thus rendering irrelevant the ability to seduce — and then choose two offspring from each pair to put into the next generation. This way everyone has the same number of surviving children. Furthermore, you give everybody a life of luxury and ease, so finding food isn’t a problem. After repeating this for a number of generations, you make life difficult again, and see what happens. You’ll discover that now the fruit fly has great difficulty trying to survive.


For some two million years of our evolution our brains became larger. John Hawks, anthropologist at the University of Wisconsin, says there has been a dramatic reversal. Over the past 20,000 years, the average volume of the human male brain has decreased from 1,500 cubic centimeters to 1,350 cc, losing a chunk the size of a tennis ball. This is major downsizing in an evolutionary eye blink. Hawks claims that If our brain keeps dwindling at that rate over the next 20,000 years, it will start to approach the size of that found in Homo erectus, a relative that lived half a million years ago and had a brain volume of only 1,100 cc.

John Hawks and a small circle of paleontologists have observed this shrinkage in their research but are unsure what it means. This brings us the “idiocracy theory” of cognitive scientist David Geary of the University of Missouri. Geary is referring to the eponymous 2006 film by Mike Judge about an ordinary guy who becomes involved in a hibernation experiment at the dawn of the 21st century. When he wakes up  500 years later, he is easily the smartest person on the dumbed-down planet. “I think something a little bit like that happened to us,” Geary says. In other words, idiocracy is where we are now.

A study he conducted with a colleague, Drew Bailey, led Geary to this epiphany. The aim of their investigation was to explore how cranial size changed as our species adapted to an increasingly complex social environment between 1.9 million and 10,000 years ago. Since that period predates the first alphabets, the researchers had no written record with which to gauge the social milieu of our predecessors. Consequently, the Missouri team used population density as a proxy for social complexity, reasoning that when more people are concentrated in a geographic region, trade springs up between groups, there is greater division of labor, the gathering of food becomes more efficient, and interactions among individuals become richer and more varied.

Bailey and Geary found population density did indeed track closely with brain size, but in a surprising way, when population numbers were low, as was the case for most of our evolution, the cranium kept getting bigger. But as population went from sparse to dense in a given area, cranial size declined, highlighted by a sudden drop around 15,000 to 10,000 years ago.

The observation led the researchers to a radical conclusion: As complex societies emerged, the brain became smaller because people did not have to be as smart to stay alive. As Geary explains, individuals who would not have been able to survive by their wits alone could scrape by with the help of others—supported, as it were, by the first social safety nets. Consequently, as society became more and more complex so did the social safety nets which proliferated and became more and more sophisticated and comprehensive. Like the birds on remote islands that lost their ability to fly, we are becoming a species that is losing its ability to think because we no longer have to think in order to survive.


  1. I don’t want to discount the interesting article. I enjoyed the read. These are just the things that are produced in my mind while reading it. Thanks for all the articles. I’ve enjoyed reading your site.

  2. A few things come to mind while reading this.

    1)that population density increase and the subdivision of labor could allow smaller brains to accomplish more. This could make a smaller brain more productive over all.

    2) An evolving wiring of the brain could have made a larger brain less advantageous. My cell phone has more ‘intelligence’ than the first room sized computers.

    3) Perhaps the issues you mentioned didn’t “cause” smaller brains but “allowed” smaller brains. There’s no conclusive proof that larger brains did more processing than is done currently.

Comments are closed.