1. Clifford A. Pickover suggests that there is intelligent life on other planets because the same physical and chemical forces that brought about life on Earth exist throughout the universe. Mark Wolverton maintains that the evolution of life depends on such a complex convergence of factors that the existence of intelligent beings elsewhere is unlikely. Do you agree or disagree with Wolverton that the complexity of factors enabling evolution casts doubt on the existence of intelligent aliens? Support your answer with evidence from the text.
2. Philip J. Klass argues that the vast majority of UFOs can be explained as natural occurrences and therefore scientists should remain skeptical about the existence of alien spacecraft. In Greg Sandow’s discussion of his experiences as a UFO investigator, what possible mundane explanations does he consider? In his view, why should scientists maintain open minds about the possibility of extraterrestrial...