Whereas many philosophers and theologians appear to possess an emotional attachment to their theories and ideas which requires them to believe them, most scientists tend to regard their ideas differently. They are interested in formulating many logically consistent possibilities, leaving any judgment regarding their truth to observation. Scientists feel no qualms about suggesting different but mutually exclusive explanations for the same phenomenon.

John Barrow and Frank Tipler, The Anthropic Cosmological Principle, Oxford, 1986, p. 15