The biblical book of Genesis clearly defines it when Cain kills his brother Abel out of jealousy. Evil is a choice to make another suffer. As long as human beings have walked, evil has been close by.

Confronting Evil by Bill O’Reilly and Josh Hammer recounts the deeds of the worst people in history: Genghis Khan. The Roman Emperor Caligula. Henry VIII. The collective evil of the 19th century slave traders and the 20th century robber barons. Stalin. Hitler. Mao. The Ayatollah Khomeini. Putin. The Mexican drug cartels. Collectively, these warlords, tyrants, businessmen, and criminals are directly responsible for the death and misery of hundreds of millions of people.

By telling what they did and why they did it, Confronting Evil explains the struggle between good and evil–a choice every person in the Judeo-Christian tradition is compelled to make. But many defer. We avoid the life decision. We look away. It’s easier.

Prepare yourself to read the consequences of that inaction. As John Stuart Mill said in his inaugural address to the University of St. Andrews in 1867: “Bad men need nothing more to compass their ends, than that good men should look on and do nothing.”