All his life, Carl Sagan was troubled by grand dichotomies—between reason and irrationalism, between wonder and skepticism. The dichotomies clashed within him.
. . . In the final analysis, he was the dichotomy: the prophet and the hard-boiled skeptic, the boyish fantasist and the ultrarigorous analyst, the warm companion and the brusque colleague, the oracle whose smooth exterior concealed inner fissures, which, in the end, only one woman would heal.Keay Davidson, Carl Sagan: A life, p. 1