A certain kind of scientific candor is a very important quality, and it is one which can hardly exist in a man who imagines that there are things which it is his duty to believe. We cannot, therefore, really decide whether religion does good without investigating the question whether religion is true. To Christians, Mohammedans, and Jews the most fundamental question involved in the truth of religion is the existence of God. In the days when religion was still triumphant the word "God" had a perfectly definite meaning; but as a result of the onslaughts of the Rationalists the word has become paler and paler, until it is difficult to see what people mean when they assert that they believe in God.
Source: Bertrand Russell: Has Religion Made Useful Contributions to Civilization? 1930.
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