Moralists, of course, do not think out the consequences of advocating a morality which they know will not be obeyed; they think that so long as they do not advocate prostitution, they are not responsible for the fact that prostitution is the inevitable outcome of their teaching. This, however, is only another illustration of the well-known fact that the professional moralist in our day is a man of less than average intelligence.
Source: Bertrand Russell :Marriage and Morals, 1929
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