If your child is ill, you may be unhappy, but you will not feel that all is vanity; you will feel that the restoring of the child to health is a matter to be attended to regardless of the question whether there is ultimate value in human life or not. A rich man may, and often does, feel that all is vanity, but if he should happen to lose his money, he would feel that his next meal was by no means vanity.
Source: The Conquest of Happiness, 1930, chap.2: Byronic unhappiness.
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