But now please observe how "the whirligig of time brings its
revenges." This latest discovery of the remedial virtue of a
very, very tiny hair of the dog that bit you reminds us, not only
of Arndt's law of protoplasmic reaction to stimuli, according to
which weak and strong stimuli provoke opposite reactions, but of
Hahnemann's homeopathy, which was founded on the fact alleged by
Hahnemann that drugs which produce certain symptoms when taken in
ordinary perceptible quantities, will, when taken in
infinitesimally small quantities, provoke just the opposite
symptoms; so that the drug that gives you a headache will also
cure a headache if you take little enough of it. I have already
explained that the savage opposition which homeopathy encountered
from the medical profession was not a scientific opposition; for
nobody seems to deny that some drugs act in the alleged manner.
It was opposed simply because doctors and apothecaries lived by
selling bottles and boxes of doctor's stuff to be taken in
spoonfuls or in pellets as large as peas; and people would not
pay as much for drops and globules no bigger than pins' heads.
Nowadays, however, the more cultivated folk are beginning to be
so suspicious of drugs, and the incorrigibly superstitious people
so profusely supplied with patent medicines (the medical advice
to take them being wrapped round the bottle and thrown in for
nothing) that homeopathy has become a way of rehabilitating the
trade of prescription compounding, and is consequently coming
into professional credit. At which point the theory of opsonins
comes very opportunely to shake hands with it.

Add to the newly triumphant homeopathist and the opsonist that
other remarkable innovator, the Swedish masseur, who does not
theorize about you, but probes you all over with his powerful
thumbs until he finds out your sore spots and rubs them away,
besides cheating you into a little wholesome exercise; and you
have nearly everything in medical practice to-day that is not
flat witchcraft or pure commercial exploitation of human
credulity and fear of death. Add to them a good deal of
vegetarian and teetotal controversy raging round a clamor for
scientific eating and drinking, and resulting in little so far
except calling digestion Metabolism and dividing the public
between the eminent doctor who tells us that we do not eat enough
fish, and his equally eminent colleague who warns us that a fish
diet must end in leprosy, and you have all that opposes with any
sort of countenance the rise of Christian Science with its
cathedrals and congregations and zealots and miracles and cures:
all very silly, no doubt, but sane and sensible, poetic and
hopeful, compared to the pseudo science of the commercial general
practitioner, who foolishly clamors for the prosecution and even
the execution of the Christian Scientists when their patients
die, forgetting the long death roll of his own patients.

By the time this preface is in print the kaleidoscope may have
had another shake; and opsonin may have gone the way of
phlogiston at the hands of its own restless discoverer. I will
not say that Hahnemann may have gone the way of Diafoirus; for
Diafoirus we have always with us. But we shall still pick up all
our knowledge in pursuit of some Will o' the Wisp or other. What
is called science has always pursued the Elixir of Life and the
Philosopher's Stone, and is just as busy after them to-day as
ever it was in the days of Paracelsus. We call them by different
names: Immunization or Radiology or what not; but the dreams
which lure us into the adventures from which we learn are always
at bottom the same. Science becomes dangerous only when it
imagines that it has reached its goal. What is wrong with priests
and popes is that instead of being apostles and saints, they are
nothing but empirics who say "I know" instead of "I am learning,"
and pray for credulity and inertia as wise men pray for
scepticism and activity. Such abominations as the Inquisition and
the Vaccination Acts are possible only in the famine years of the
soul, when the great vital dogmas of honor, liberty, courage, the
kinship of all life, faith that the unknown is greater than the
known and is only the As Yet Unknown, and resolution to find a
manly highway to it, have been forgotten in a paroxysm of
littleness and terror in which nothing is active except
concupiscence and the fear of death, playing on which any trader
can filch a fortune, any blackguard gratify his cruelty, and any
tyrant make us his slaves.

Lest this should seem too rhetorical a conclusion for our
professional men of science, who are mostly trained not to
believe anything unless it is worded in the jargon of those
writers who, because they never really understand what they are
trying to say, cannot find familiar words for it, and are
therefore compelled to invent a new language of nonsense for
every book they write, let me sum up my conclusions as dryly as
is consistent with accurate thought and live conviction.

1. Nothing is more dangerous than a poor doctor: not even a poor
employer or a poor landlord.

2. Of all the anti-social vested interests the worst is the
vested interest in ill-health.

3. Remember that an illness is a misdemeanor; and treat the
doctor as an accessory unless he notifies every case to the
Public Health authority.

4. Treat every death as a possible and under our present system a
probable murder, by making it the subject of a reasonably
conducted inquest; and execute the doctor, if necessary, as a
doctor, by striking him off the register.

5. Make up your mind how many doctors the community needs to keep
it well. Do not register more or less than this number; and
let registration constitute the doctor a civil servant with a
dignified living wage paid out of public funds.

6. Municipalize Harley Street.

7. Treat the private operator exactly as you would treat a
private executioner.

8. Treat persons who profess to be able to cure disease as you
   treat fortune tellers.

9. Keep the public carefully informed, by special statistics and
announcements of individual cases, of all illnesses of doctors
or in their families.

10. Make it compulsory for a doctor using a brass plate to have
inscribed on it, in addition to the letters indicating his
qualifications, the words "Remember that I too am mortal."

11. In legislation and social organization, proceed on the
principle that invalids, meaning persons who cannot keep
themselves alive by their own activities, cannot, beyond
reason, expect to be kept alive by the activity of others.
There is a point at which the most energetic policeman or
doctor, when called upon to deal with an apparently drowned
person, gives up artificial respiration, although it is never
possible to declare with certainty, at any point short of
decomposition, that another five minutes of the exercise would
not effect resuscitation. The theory that every individual
alive is of infinite value is legislatively impracticable. No
doubt the higher the life we secure to the individual by wise
social organization, the greater his value is to the
community, and the more pains we shall take to pull him
through any temporary danger or disablement. But the man who
costs more than he is worth is doomed by sound hygiene as
inexorably as by sound economics.

12. Do not try to live for ever. You will not succeed.

13. Use your health, even to the point of wearing it out. That is
what it is for. Spend all you have before you die; and do not
outlive yourself.

14. Take the utmost care to get well born and well brought up.
This means that your mother must have a good doctor. Be
careful to go to a school where there is what they call a
school clinic, where your nutrition and teeth and eyesight and
other matters of importance to you will be attended to. Be
particularly careful to have all this done at the expense of
the nation, as otherwise it will not be done at all, the
chances being about forty to one against your being able to
pay for it directly yourself, even if you know how to set
about it. Otherwise you will be what most people are at
present: an unsound citizen of an unsound nation, without
sense enough to be ashamed or unhappy about it.