Reductio ad Absurdum
1. Marc Antony’s funeral oration, quoted in a Discussion Question in Chapter 2, uses several reductio ad absurdum arguments to refute Brutus’s claim that Caesar was ambitious. Are these reductios deep or shallow? How could Brutus respond?
2. The legal case of Plessy v. Ferguson, 163 U.S. 537 , questioned the constitutionality of a law requiring racial segregation in railroad cars. Opponents of the law gave the following reductio argument. How could defenders of segregation respond to this argument? Is their response adequate? Is any response adequate? Why or why not?
The same argument that will justify the state legislature in requiring railways to provide separate accommodations for the two races will also authorize them to require separate cars to be provided for people whose hair is of a certain color, or who are aliens, or who belong to certain nationalities, or to enact laws requiring colored people to walk upon one side of the street, and white people upon the other, or requiring white men’s houses to be painted white, and colored men’s black, or their vehicles or business signs to be of different colors, upon the theory that one side of the street is as good as the other, or that a house or vehicle of one color is as good as one of another color.
3. Many atheists try to refute belief in God with the following reductio ad absurdum argument: God is defined to be all-good and all-powerful (as well as all-knowing). If God is all-good, then God prevents as much evil as He can. If God is all-powerful (and all-knowing), then God can prevent all evil. Thus, if a traditional God did exist, there would be no evil in the world. But that’s absurd. There is obviously lots of evil in the world. Therefore, God does not exist. (Compare Chapter 21 in Part V on Religious Reasoning.) Evaluate this reductio argument. How could religious believers best respond?
