Starting the spring of my 23rd year, I spent 13 months straight in East Asia, teaching English and traveling through South Korea, Japan, and China.

As a 6'3'' blonde guy, it was pretty obvious that I looked different than just about everybody else.

What was less obvious is that as a Westerner, I thought differently than my new East Asian friends. Contracts, agreements, appointments — the cultural differences were huge.

According to cultural philosophers, Westerners and East Asians have had contrasting views about the concept of truth and how it works for thousands of years — and it shows up in present-day psychology.

It all goes back to the cradles of two civilizations: ancient Greece and ancient China.

It comes down to two different "laws":

• The Greeks followed the "law of the excluded middle," which states that if two people are debating, then one of them must be exclusively right and the other exclusively wrong.

• The Chinese followed the "doctrine of mean," which states that if two people are debating, then they're probably both partly right and partly wrong — the truth probably lies somewhere in the middle.

These things have deep roots.

The doctrine of the mean dates back to Confucius, who lived some 2,500 years ago. It is "widely considered as the highest ideal in Confucianism," write scholars Li-Jun Ji, Albert Lee, and Tieyuan Guo in "The Oxford Handbook of Chinese Psychology."

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"Accordingly, Chinese are encouraged to argue for both sides in a debate (i.e. both arguments are correct), or to assign equal responsibilities in a dispute (i.e. no party is at complete fault)," they write. "This presents an interesting contrast with the law of the excluded middle in Western philosophies, according to which one ought to eliminate ambiguity or inconsistency by selecting one and only one of the conflicting ideas. Unlike the Chinese tradition, it assumes no merit in the middle ground."

The "law of the excluded middle" has a very fancy Latin name: principium tertii exclusi.

Aristotle wrote about it in his "Ethics" about 2,300 years ago.

"There cannot be an intermediate between contradictories," he wrote, "but of one subject we must either affirm or deny any one predicate."

Incredibly, those ancient takes on truth show up in present-day psychology experiments.

In a widely cited 1999 paper, psychologists Kaiping Peng and Richard E. Nisbett gave Chinese and American college students a range of scenarios describing conflicts between people and asked for advice about how to resolve them.

As Confucianism would suggest, the Chinese students were more likely to give "dialectical" responses, or seeing truth and fault in both parties.

One prompt was a family conflict:

Mary, Phoebe, and Julie all have daugthers. Each mother has held a set of values which has guided her efforts to raise her daugther. Now the daugthers have grown up, and each of them is rejecting many of her mother's values. How did it happen and what should they do?

The responses were remarkably different:

• 72% of Chinese students gave compromise-oriented responses, like "both the mothers and the daugthers have failed to understand each other"

• 74% of Americans found fault on one side, with responses like "mothers have to recognize daugthers' rights to their own values."

Just as the differences between Confucius and Aristotle would suggest, Easterners and Westerners had different approaches to conflict.

But those approaches didn't fall from the sky. They came from culture.

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