This aversion to noise I should explain as follows: If you cut up a large diamond into little bits, it will entirely lose the value it had as a whole; and an army divided up into small bodies of soldiers, loses all its strength. So a great intellect sinks to the level of an ordinary one, as soon as it is interrupted and disturbed, its attention distracted and drawn off from the matter in hand; for its superiority depends upon its power of concentration — of bringing all its strength to bear upon one theme, in the same way as a concave mirror collects into one point all the rays of light that strike upon it. Noisy interruption is a hindrance to this concentration. That is why distinguished minds have always shown such an extreme dislike to disturbance in any form, as something that breaks in upon and distracts their thoughts. Above all have they been averse to that violent interruption that comes from noise. Ordinary people are not much put out by anything of the sort. The most sensible and intelligent of all nations in Europe lays down the rule, Never Interrupt! as the eleventh commandment. Noise is the most impertinent of all forms of interruption. It is not only an interruption, but also a disruption of thought. Of course, where there is nothing to interrupt, noise will not be so particularly painful. Occasionally it happens that some slight but constant noise continues to bother and distract me for a time before I become distinctly conscious of it. All I feel is a steady increase in the labor of thinking — just as though I were trying to walk with a weight on my foot. At last I find out what it is.

The belief that humanity makes moral progress depends upon a wilful ignorance of history. It also depends upon a wilful ignorance of oneself – a refusal to recognise the extent to which selfishness and calculation reside in the heart even of our most generous emotions, awaiting their chance. Those who invest their hopes in the moral improvement of humankind are therefore in a precarious position: at any moment the veil of illusion might be swept away, revealing the bare truth of the human condition. Either they defend themselves against this possibility with artful intellectual ploys, or they give way, in the moment of truth, to a paroxysm of disappointment and misanthropy. Both of these do violence to our nature. The first condemns us to the life of unreason; the second to the life of contempt. Human beings may not be as good as the shallow optimists pretend; but nor are they as bad as the prophets and curmudgeons have painted them.