226 



DISCOVERY 



many years — occurring in the year in which the names 

 of Jenner and Pasteur are celebrated, is a serious 

 commentary on the generation which, inheriting their 

 great discoveries, has neglected to take advantage 

 of them. A very large percentage of the population 

 of England to-day is un-vaccinated ; a very small 

 percentage has taken the essential precaution of re- 

 vaccination. We do not know the terrors of small-pox 

 because our fathers took the trouble to become vacci- 

 nated ; our children will doubtless rediscover them 

 through our omission to do so. The danger involved 

 in this simple process is probably much less than is 

 incurred by anyone who suffers a scratch with a pin — 

 for in that case there is always the chance of infection ; 

 while with the simple precaution of cleanliness vaccina- 

 tion causes at most a day or two of inconvenience. 

 ***** 

 It would be interesting to attempt an analysis of 

 the mental processes of those who belong to that 

 surprisingly large body of people who disbelieve in 

 practically every advance in medical knowledge for 

 the last hundred years. They are not, of course, a 

 production of this age alone. The history of all 

 learning is marked far more by tales of the oppression 

 and even martyrdom of the discoverer of new things 

 than by the gratitude of those who are emancipated 

 or enlightened. We can always hear — 



The cry of these ye humour 

 Ah, slowly, to the light, 

 ' Why brought ye us from darkness. 

 Our loved Egyptian night ? ' " 



The fact that there is a party in politics calling 

 themselves Conservatives — we speak with no political 

 bias whatever — and that they have a subdivision 

 known as " Die-hards," who, in the words of Punch, 

 j^early die in a fresh ditch, indicates that opposition 

 to any new thing is a fixed habit of the mind of men. 

 The simplest virtue is changelessness. " A stopped 

 clock is right twice in twenty-four hours," but this 

 spirit of stolid immobility, which has certainly its uses 

 in preventing too precipitate a course of action in 

 politics and social matters, is not the only factor in 

 the opposition to the theories of modern medicine. 

 There is a distortion of reasoning evident in the per- 

 petual demand for " proof " of the efficacy of this or 

 that process. " Proof " is a relative thing. Apart 

 from certain mathematical statements, few facts are 

 susceptible of " proof " in the most rigid sense of 

 the word. Where a human factor is involved, the 

 difficulties of proof are infinite. There are people 

 who, like the Scotch visitor to the Zoo, can look at 

 an elephant and say, " I don't believe it." Only a 

 few centuries ago, " proof " in scientific matters really 

 meant that Aristotle had made a definite statement 



on the point. Strangely enough, few were then suffi- 

 ciently brave to say, " I don't believe Aristotle." But 

 to-day, when each man has better opportunities of 

 investigating the grounds for belief in a statement 

 made by a scientist, a large number of people are ready 

 to disbelieve it without anj- investigation at all. 

 ***** 

 In the case of the treatment and the prevention of 

 disease, " proof " is a hundredfold more difficult than 

 in the case, for example, of a statement that a gas 

 expands in a regular manner when heated. The 

 doctor deals with living creatures. There is only one 

 statement which can be made with absolute certainty 

 about a living creature, and that is that it will die. 

 We are not sure whether a certain sect of Christian 

 Scientists admit even that much. The argument in 

 favour of vaccination, of typhoid inoculation, of the 

 germ theory of disease, rests on the record of a vast 

 series of observations favourable to them. On the 

 other hand, there are many facts in each case, many 

 examples of apparent failure, which point in an 

 opposite direction. Thus, any discussion of the efficacy 

 of a curative or preventive method quickly becomes 

 a battle of statistics. No one ever reads statistics. 

 Still less does anyone verify them ; they are merely 

 the ammunition of the combat, for the vaccinationist 

 and the anti-vaccmationist, the bacteriologist and the 

 anti-bacteriologist. In many cases, one group of 

 figures refers to a condition of affairs completely 

 different from those dealt with by opposition figures. 

 For ejcample, anti-vaccinationists perpetually bring 

 forward the case of the Philippine Islands, where, after 

 many years of the apparent prevention of small-pox, 

 it again broke out with redoubled vigour. The facts 

 are that, during the period in which it was successfully 

 prevented, vaccination was done by United States 

 officials ; when it broke out, vaccination was being 

 neglected under the auspices of the local authorities. 

 ***** 



Of course, the belief which a doctor or a layman holds 

 in the value of a well-tried method of cure or preven- 

 tion rests in " statistics," or facts which might be 

 expressed as an imposing mathematical table. But that 

 belief rests also on a wide experience, a knowledge of 

 the thousand-and-one factors which have intruded in 

 each separate case. There are very few doctors among 

 the disbelievers in the theories of modern medicine. 

 It is often said that this is because it pays them to 

 believe in them, and to practise their teaching. Every 

 doctor, however, knows that there is far more money to 

 be made by following any one of a hundred will-o'-the- 

 wisps of quackery than in the narrow path of the 

 learning bequeathed by Jenner, Pasteur, and Lister. 

 Life is as much a puzzle to the doctor as the weather 



