Reflecting upon yesterday's tragedy, the bombing at the 2013 Boston Marathon, had me looking up Thomas Aquinas inquiry into the problem of good and evil. I found reflection in Summa Theologica, Part I, Question 49, Article 1. Aquinas explains evil as the absence of good, depending upon the species. That's depending where it properly belongs. It is bolded because good (it) can be perceived differently. A baby not walking at two would be perceived as bad. But that same baby finally walking at three, would be good.
Aquinas also thinks that the world is better for having evil within it. If it never rained, we wouldn't appreciate the sun. If the bomb going off at the Boston Marathon didn't go off, heroes wouldn't have rushed in. Stories abound about the bystanders and runners rushing to help.
If I, personally, had been affected by this bomb, of course, Aquinas' argument that the world is better with evil, would be an anathema. I would just want my loved ones, the world, bomb free. God wouldn't want harm to come to his creatures. And Aquinas would agree. God's goodness is beyond all definition of good, and we can't hold God accountable for man's free choice. It's that damn free will!
Some human, lacking my understanding of good, chose to terrorize the Boston Marathon. Aquinas does not reason that we can choose evil. The terrorist thinks he is doing good.
Regardless, I hope that terrorist is prepared to suffer for his understanding of good, because he broke society's laws, never mind God's fifth commandment. He may in his personal code of morality, think he is doing good. But he isn't. He is a threat to the common good of society, and will be punished by society's law.