After Robert Mugabe, Zimbabwe’s despotic president, was overthrown late Tuesday night, some commentators expressed cautious optimism that regime change might be good news for the country. Military historian Rut Diamint of Argentina – a country painfully acquainted with military rule – brings a distinct perspective to the question of whether a coup d’etat can help democratize a nation. Her answer: Don’t count on it. Latin America’s 20th-century military dictatorships were bloody national traumas. Even now, 40 years later, the cultural legacy of totalitarianism continues to undermine democracy across the region.

Every so often you might hear a pundit asserting that some group or other is just like Pavlov’s dogs, unthinkingly responding to some event. Psychologist Edward Wasserman explains how, contrary to this negative characterization, the basic learning process first studied in Pavlov’s drooling dogs holds the key to understanding many of our most important emotional experiences.

Yesterday, the House approved a $1.5 trillion tax cut. The enormity of a number like that is tough for most of us to wrap our heads around. Andrew Hwang, a mathematics professor at College of the Holy Cross, shares his tricks for breaking down the massive numbers in the millions, billions and trillions that fill today’s news stories.