Click here to sign up

The New York Times for more than a decade. With an eye for quirky topics
and  a  deft  narrative  style,  Grady  won  numerous  journalism  prizes  by
making esoteric topics accessible to lay readers.
That  day,  one  of  Grady’s  articles  rocketed  up  the  newspaper’s  Most  E-
Mailed list. Within hours of its publication thousands of people had decided
to pass on the article to their friends, relatives, and coworkers. Grady had
scored a viral hit.
The  topic?  How  fluid  and  gas  dynamic  theories  were  being  used  in
medical research.
Grady’s article detailed something called schlieren photography, in which
“a  small,  bright  light  source,  precisely  placed  lenses,  a  curved  mirror,  a
razor  blade  that  blocks  part  of  the  light  beam  and  other  tools  make  it
possible to see and photograph disturbances in the air.”
Sounds  less  than  riveting,  right?  Join  the  club.  When  we  asked  people
what they thought of this article on a number of different dimensions, the
scores were pretty low. Did it have lots of Social Currency? No, they said.
Did  it  contain  a  lot  of  practically  useful  information  (something  we’ll
discuss in the Practical Value chapter)? No again.
In fact, if you’d gone down the checklist of characteristics traditionally
believed to be prerequisites for viral content, Grady’s article, entitled “The
Mysterious Cough, Caught on Film,” would have lacked most of them. Yet
Grady’s  piece  clearly  had  something  special  or  so  many  people  wouldn’t
have hit the e-mail button. What was it?
—————
Grady’s  interest  in  science  started  in  high  school.  She  was  sitting  in
chemistry class when she read about Robert Millikan’s famous experiment
to determine the charge on a single electron. It was a complicated idea and a

---

complicated experiment. The study involved suspending tiny droplets of oil
between two metal electrodes, then measuring how strong the electric field
had to be in order to stop the droplets from falling.
Grady read it several times. Again and again until she finally understood.
But when she did, it was like a flash going off. She got it. It was thrilling.
The thinking behind the experiment was so clever, and being able to grasp it
was enthralling. She was hooked.
After school Grady went to work at Physics Today magazine. Eventually
she worked at Discover and Time magazine and finally worked her way up
to health editor at The New York Times. The goal of her articles was always
the same: to give people even just a little bit of that excitement that she had
felt back in chemistry class decades before. An appreciation for the magic
of scientific discovery.
In her piece that October, Grady described how an engineering professor
used  a  photographic  technique  to  capture  a  visible  image  of  a  seemingly
invisible phenomenon—a human cough. The schlieren technique had been
used  for  years  by  aeronautics  and  military  specialists  to  study  how  shock
waves form around high-speed aircraft. But the engineering professor had
harnessed the technique in a new way: to study how airborne infections like
tuberculosis, SARS, and influenza spread.
It  made  sense  that  most  people  thought  the  article  wasn’t  particularly
useful. After all, they weren’t scientists studying fluid dynamics. Nor were
they engineers trying to visualize complex phenomena.
And  while  Grady  is  one  of  the  best  science  writers  out  there,  it  made
sense  that  the  general  population  would  tend  to  be  more  interested  in
articles about sports or fashion. Finally, while coughs would certainly be a
nice  trigger  to  remind  people  of  the  article,  cold  and  flu  season  tends  to
peak around February, four months after the article was released.
Even  Grady  was  bemused.  As  a  journalist,  she’s  delighted  when
something she writes goes viral. And like most journalists, or even casual
bloggers,  she’d  love  to  understand  why  some  of  her  pieces  get  widely
shared while others don’t.
But while she could make some educated guesses, neither she nor anyone
else really knew why one piece of content gets shared more than another.
What made this particular article go viral?
—————

---

After years of analysis, I’m happy to report that my colleagues and I have
some answers. Grady’s 2008 article was part of a multi-year study in which
we analyzed thousands of New York Times articles to better understand why
certain pieces of online content are widely shared.
A  clue  comes  from  the  picture  that  accompanied  Grady’s piece. Earlier
that October, she had been scanning an issue of The New England Journal