on the legacy of the experiment = on the legacy of the 1971 experiment?

What does "went to great lengths " mean?

Context:


Using the Psychology of Evil To Do Good
Forty years after the infamous Stanford Prison Experiment, Phil Zimbardo thinks he can apply its lessons to teach ordinary people to be heroes

When the disturbing photos of American
soldiers mistreating prisoners at Abu Ghraib
prison in Iraq began leaking out 7 years ago
this week, they jolted Philip Zimbardo with
a sickening sense of déjà vu. The naked-
ness of the prisoners and the bags over their
heads, the shamelessness and perverse cre-
ativity of the captors—he’d seen much of
this before. In 1971, as a psychology pro-
fessor at Stanford University in Palo Alto,
California, Zimbardo presided over one of
the best-known experiments in the history
of social psychology. He sequestered 24
student volunteers in a boarded-up corridor
in the basement of Jordan Hall, randomly
assigning half to be guards and half to be
prisoners. Six days into an experiment that
was supposed to run for 2 weeks, Zimbardo
had to call it off because the prisoner abuse
had gotten so bad.
By 2004, Zimbardo had put the Stan-
ford Prison Experiment behind him. But as
the Abu Ghraib story unfolded, he slowly
became a part of it, fi rst through media inter-
views on prison psychology, and then as an
expert witness in the trial of staff sergeant

Ivan “Chip” Frederick, the highest ranking
soldier charged for the abuse. The experi-
ence caused him to reexamine the prison
experiment and question his own role in it.
It also gave Zimbardo inspiration for
his next big experiment. At age 78, he has
reinvented himself as a social entrepreneur,
leading a new project that will attempt to
turn the Stanford Prison Experiment and
other studies of the dark side of the human
psyche into a force for good. Last year,
Zimbardo founded the Heroic Imagina-
tion Project, which operates out of a for-
mer Army post in San Francisco’s Presidio
park. Its goal is to use lessons learned from
social psychology research to teach ordinary
people—from high school students to offi ce
workers—to recognize the infl uences that
can make people stand idly by when they
see a person in need and embolden them to
commit what Zimbardo calls acts of every-
day heroism. The organization has plans
for teaching, research, and public outreach
that are just getting off the ground. “Our
ambition is to seed the world with heroes,”
Zimbardo says.

Taking prisoners
To mark the 40th anniversary of the Stanford
Prison Experiment this summer, the Ameri-
can Psychological Association will host a
symposium on the legacy of the experiment at its annual meeting. The original goal was
to investigate what happens when good peo-
ple fi nd themselves in a bad situation. “We
went to great lengths to put good apples in
a bad barrel,” Zimbardo says. All the guards
(and prisoners) were healthy young men
with no history of psychological problems,
drug abuse, or run-ins with the law. The
question was: “Does the goodness of the
apples dominate, or does the badness of the
barrel corrupt?”
The first day passed without incident.
But on the second day the prisoners rebelled,
taking off their numbers and barricading
themselves in a cell. The guards called in
reinforcements, conducted strip searches,
and put the ringleaders in solitary confi ne-
ment. The guards’ treatment grew harsher in
the following days as they forced prisoners to
do pushups, limited their access to the toilet,
and used psychological tactics to break down
solidarity. Thirty-six hours into the experi-
ment, one prisoner suffered a breakdown,
crying, screaming, and cursing. Zimbardo
suspected he was faking but sent him home.
Over the following days, Zimbardo says at
least 50 people came to see what was going
on in the basement of Jordan Hall, includ-
ing colleagues in the psychology depart-
ment and parents and friends of the prisoners.
Most didn’t see the worst of the abuses, but