Our chosen group of "greater" scientists were members of the National Academy of Sciences (NAS). Our survey found near universal rejection of the transcendent by NAS natural scientists. Disbelief in God and immortality among NAS biological scientists was 65.2% and 69.0%, respectively, and among NAS physical scientists it was 79.0% and 76.3%. Most of the rest were agnostics on both issues, with few believers. We found the highest percentage of belief among NAS mathematicians (14.3% in God, 15.0% in immortality). Biological scientists had the lowest rate of belief (5.5% in God, 7.1% in immortality), with physicists and astronomers slightly higher (7.5% in God, 7.5% in immortality).

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Because of the relatively small size of NAS membership, we sent our survey to all 517 NAS members in those core disciplines. Leuba obtained a return rate of about 70% in 1914 and more than 75% in 1933 whereas our returns stood at about 60% for the 1996 survey and slightly over 50% from NAS members [1,2].