It's called "ceiling time" at Eastern Correctional facility in New York's Hudson Valley—those minutes between heading back to one's cell and falling asleep.
One even started recently over disagreements about a German American political theorist.
"We were talking about Hannah Arendt, working out one day, and it was a very, very vicious, violent argument. We were just attacking each other on what it means to be a human being and stuff like that.
I've watched him over the years really become a transformed person.
He's gotten in touch with his intellectual ability.
The founder and executive director of BPI, Max Kenner, says it took Pérez four tries just to get into the rigorous program. But most importantly says Kenner, when he gets out, he's more likely to be "a middle class tax paying person, who is a neighbor, and a family member, and perhaps in time a father, and a full civic citizen who is living as fulfilling a life as possible." Although Pérez will soon have a wife as well as a college degree, he can't entirely escape the reality of being in prison.