Americans and Europeans stand out from the rest of the world for our sense of ourselves as individuals. We like to think of ourselves as unique, autonomous, self-motivated, self-made. As the anthropologist Clifford Geertz observed, this is a peculiar idea.
People in the rest of the world are more likely to understand themselves as interwoven with other people - as interdependent, not independent. In such social worlds, your goal is to fit in and adjust yourself to others, not to stand out.
People imagine themselves as part of a larger whole - threads in a web, not lone horsemen on the frontier. In America, we say that the squeaky wheel gets the grease. In Japan, people say that the nail that stands up gets hammered down.
These are broad brush strokes, but the research demonstrating the differences is remarkably robust and it shows that they have far-reaching consequences.
Social psychologist Richard E. Nisbett and his colleagues found that these different orientations towards independence and interdependence affected cognitive processing. For example, Americans are more likely to ignore the context, and Asians to attend to it. Show an image of a large fish swimming among other fish and seaweed fronds, and the Americans will remember the single central fish first. That's what sticks in their minds.
Japanese viewers will begin their recall with the background. They'll also remember more about the seaweed and other objects in the scene.
Social psychologist Hazel Rose Markus asked people arriving at San Francisco International Airport to fill out a survey and offered them a handful of pens to use, for example four orange and one green; those of European descent more often chose the one pen that stood out, while the Asians chose the one more like the others.
Dr Markus and her colleagues found that these differences could affect health. Negative affect - feeling bad about yourself - has big, persistent consequences for your body if you are a Westerner. Those effects are less powerful if you are Japanese, possibly because the Japanese are more likely to attribute the feelings to their larger situation and not to blame themselves.
There's some truth to the modernisation hypothesis - that as social worlds become wealthier, they also become more individualistic - but it does not explain the persistent interdependent style of Japan, South Korea and Hong Kong.
In May, the journal Science published a study, led by young University of Virginia psychologist Thomas Talhelm, that ascribed these different orientations to the social worlds created by wheat farming and rice farming. Rice is a finicky crop. Because rice paddies need standing water, they require complex irrigation systems that have to be built and drained each year. One farmer's water use affects his neighbour's yield. A community of rice farmers needs to work together in tightly integrated ways.
Not wheat farmers. Wheat needs only rainfall, not irrigation. To plant and harvest it takes half as much work as rice does, and substantially less coordination and cooperation. And, historically, Europeans have been wheat farmers and Asians have grown rice.
The authors of the study in Science argue that over thousands of years, rice- and wheat-growing societies developed distinctive cultures: "You do not need to farm rice yourself to inherit rice culture."
Their test case was China, where the Yangtze River divides northern wheat growers from southern rice growers.
The researchers gave Han Chinese from these different regions a series of tasks. They asked, for example, which two of these three belonged together: a bus, a train and train tracks?
More analytical, context-insensitive thinkers (the wheat growers) paired the bus and train, because they belong to the same abstract category. More holistic, context-sensitive thinkers (the rice growers) paired the train and train tracks, because they work together.
Asked to draw their social networks, wheat-region subjects drew themselves larger than they drew their friends; subjects from rice-growing regions drew their friends larger than themselves.
Asked to describe how they'd behave if a friend caused them to lose money in a business, subjects from the rice region punished their friends less than subjects from the wheat region did.
Those in the wheat provinces held more patents; those in the rice provinces had a lower rate of divorce.
I write this from Silicon Valley, where there is little rice. The local wisdom is that all you need is a garage, a good idea and energy, and you can found a company that will change the world.
The bold visions presented by entrepreneurs are breathtaking in their optimism, but they hold little space for elders, for longstanding institutions, and for the deep roots of community and interconnection.
Nor is there much rice within the Tea Party. Senator Ted Cruz, a Republican from Texas, declared recently that all a man needed was a horse, a gun and the open land, and he could conquer the world.
Wheat doesn't grow everywhere. Start-ups won't solve all our problems. A lone cowboy isn't much good in the aftermath of a Hurricane Katrina.
As we enter a season in which the values of do-it-yourself individualism are likely to dominate our Congress, it is worth remembering that this way of thinking might just be the product of the way our forefathers grew their food and not a fundamental truth about the way that all humans flourish.
NEW YORK TIMES