Secondly, it may suffer from poisoning. This may be the result of dyspepsia, for when food lies in the stomach undigested, it is apt to ferment, producing a poison that circulates throughout the body. Or it may be because the impurities, which are found throughout the whole body, are not being got rid of, owing to a want of exercise and fresh air. Or it may be owing to undue wear and tear in consequence of a lack of sufficient rest.
Too often it is a combination of the two processes, the nervous system being attacked by starvation and poisoning at the same time.
The whole of man’s structure is a marvellous automaton, and once the nervous element is disturbed the trouble which first upset the harmony is increased tenfold.
Yet the mischief may not be apparent all at once, for the whole organisation is so accurately balanced that defects in one part will be compensated for by other organs. And whilst this is a safeguard in one way, it is a serious menace in another. For the fault is apt to be overlooked, until at last the process has gone on to such an extent that the balance is upset. The machine does not stop running, but, like a motor-car in similar circumstances, it begins to run badly. The man himself becomes what is called “run down.”
It is a provision of Nature that the nervous system, being the mainspring of our existence, holds out longer than any other structure in the body. If it did not do so most of us would have been dead or broken down long ago. Yet it means that when the loss of balance reaches such a point that compensation fails, the breakdown is all the more disastrous.
Then, when the crash comes, we blame our nerves, our civilisation, our worries and troubles, our heredity, anything in short except ourselves. Of course, there are cases in which circumstances have entered over which the patient has had no control. Sometimes neurasthenia follows a severe illness or a bad accident. Sometimes it comes on at critical periods of life. And in some instances heredity has played a part. There are some unfortunate individuals who have been born with weak frames and little stamina, so that even the ordinary conditions of life, however favourable, prove too much for them.