Metchnikoff, the noted bacteriologist, alleges that the large intestine is the breeding-place of these destructive germs. A Dr. Hall arrived at the same conclusion earlier and combated his germs with copious water-flooding of the bowels. So far, Metchnikoff’s experiments point to the conclusion that lactic acid destroys them. That is why he recommends the use of pure buttermilk and has invented a tablet that, dropped into milk, will convert it into a wholesome drink for adult man. Discoveries and inventions of this sort are of great interest to all who enjoy and seek to prolong life. But purely physical things cannot take the place of the mental attitude. The youngest woman of seventy-nine that I have ever known is one who says, “Tell me more; I must not get into such a rut that I cannot grow.” No discovery or invention will do us much good if we allow habit to cramp our thought and custom to stale it. Science may show us how to avoid disease and to prolong life, but, if we turn a deaf ear to her teaching, we shall get no benefit from it. It is the alert, open mind that profits from discovery or experience. The sun may shine with life-giving power, but, if the house be shuttered and darkened, it will not benefit the dwellers. So with the mind. If we resolutely shut it against new ideas, if we refuse to take even the gift of life and health from an unaccustomed hand, then we must expect to suffer. If we would rid ourselves of sleeplessness, of disease, and dissatisfaction, we must be willing to let go of every habit, every thought, every feeling that may injure us. To hug them to us is merely to invite further suffering, to lessen our own vigor and our own enjoyment. Nevertheless, we must hug our habits to us, if we can see or understand nothing better. No one can help us beyond what we are willing to receive: anyone can lead a horse to the water, but no one can make him drink. If the end in view seems to us worth the price we must pay, we pay it. We have no choice; for our desires push us that way. We often take credit to ourselves for things for which no credit is due us. However self-denying an act may seem, it is, after all, the thing we want most to do, else we would not do it. In the same way, if we refuse to profit by the discoveries and experiments of others, if we prefer to go on in our old way of suffering, nobody can really prevent us. It is all a matter that we must decide. This book does not pretend to cure any ill. It intends merely to show what investigation and experience have proved; to point to possible ways of escape from the ills with which men now suffer. If it looks desirable to you, you will only read it; but, until you have tried it, you cannot say whether it is good or not. CHAPTER XXXI VAIN REGRETS Thou hast been called, O Sleep! the friend of woe; But ’tis the happy that have called thee so. SOUTHEY.