As time goes on, we may forget all about our early moral training, but we shall still feel uncomfortable about certain kinds of actions, while others will give us a glow of virtue. To introspection, these feelings are mysterious, since we no longer remember the circumstances which originally caused them ; and therefore it is natural to attribute them to the voice of God in the heart. But in fact conscience is a product of education, and can be trained to approve or disapprove, in the great majority of mankind, as educators may see fit.
Source: Religion and Science, 1935, chapt. 9
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