Joy is Contagious
HARVARD’S STUDY SAYS JOY IS CONTAGIOUS!
It’s long been said that laughter is contagious, and now, it turns out, so is happiness.
Happiness is not an individual but a collective phenomenon,
according to a new study released online Thursday in the British
Medical Journal.
The study, which followed almost 5,000 people over 20 years,
found that happiness can spread through three degrees of separation
within social networks, meaning that the happiness of your friend, your
friend’s friend, and even your friend’s friend’s friend can infect you
with a good mood.
“Happiness not only spreads from person to person but also
from person to person to person,” said political scientist James H.
Fowler ’92, a professor at the University of California, San Diego and
one of the paper’s authors.
The study suggests that the happiest people are those at the
center of a social network, Fowler said the most
connected people have a greater likelihood of “catching happiness.”
Happily, the study suggests that sadness is not as easily transferred through social networks.
“Unhappiness spreads, but it doesn’t spread quite as much nor
does it spread quite as consistently as happiness,” said Harvard
Medical School professor Nicholas A. Christakis, who is a co-author of
the paper.
Harvard psychology professor Daniel T. Gilbert, a expert on happiness, called the new paper “stunning” in an e-mailed statement.
“We’ve known for some time that social relationships are the
best predictor of human happiness, and this paper shows that the effect
is much more powerful than anyone realized,” Gilbert said. “It is truly
amazing to discover that when you replace the word ‘child’ with ‘best
friend’s neighbor’s uncle,’ the sentence is still true.”
But some scholars remain skeptical about whether the new
findings are accurate. Another recent study in the BMJ cautions that
Christakis and Fowler’s happiness study may be skewed.
“Our study certainly does not refute their happiness paper,
but it just suggests some caution that if you don’t take care to
control for other factors, that you might be finding contagion where
none exists,” said Jason M. Fletcher, a professor of public health at
Yale.
Fletcher co-authored a study suggesting that perceived network
effects could be erroneous. Using the same statistical methods as the
happiness study, his study found that characteristics like acne,
headaches, and height are contagious among adolescents, indicating that
the methods used in the happiness study can produce spurious results.
“There’s no such thing as a social contagion in height,” Fletcher said.
Fletcher and his co-author, B. Cohen-Cole ’95, an economist at
the Federal Reserve Bank of Boston, suggested that the happiness study
could be biased because happy people are often friends and that their
good moods are not necessarily influenced by each other.
“Friends select people to be their friends based on similar
characteristics,” said Fletcher, “and potentially happy people choose
to be friends with other happy people.”
He added that friends are often exposed to the same
environment, including similar levels of crime, risk, and weather, and
that those external variables could influence happiness more than a
friend’s mood.
In light of these criticisms, both research groups plan to continue probing into the field of happiness with future studies.
“The whole point of science is that you want to capture a great idea but then retain healthy skepticism,” Fowler said.
