Excerpted from Oliver Wendell Holmes, Sr. Medical Essays: Homeopathy Currents in Medical Science
Border Lines of Knowledge
A medical man, as he goes about his daily business after
twenty years of practice, is apt to suppose that he treats his patients
according to the teachings of his experience.
No doubt this is true to some extent; to what extent depending
much on the qualities of the individual. But it is easy to prove that the
prescriptions of even wise physicians are very commonly founded on something
quite different from experience. Experience must be based on the permanent
facts of nature.
But a glance at the prevalent modes of treatment of any two
successive generations will show that there is a changeable as well as a
permanent element in the art of healing; not merely changeable as diseases
vary, or as new remedies are introduced, but changeable by the going out of
fashion of special remedies, by the decadence of a popular theory from which
their fitness was deduced, or other cause not more significant. There is no
reason to suppose that the present time is essentially different in this
respect from any other.
Much, therefore, which is now very commonly considered to be
the result of experience, will be recognized in the next, or in some succeeding
generation, as no such result at all, but as a foregone conclusion, based on
some prevalent belief or fashion of the time.
There are, of course, in every calling, those who go about
the work of the day before them, doing it according to the rules of their
craft, and asking no questions of the past or of the future, or of the aim and
end to which their special labor is contributing. These often consider and call
themselves practical men. They pull the oars of society, and have no leisure to
watch the currents running this or that way; let theorists and philosophers
attend to them. In the mean time, however, these currents are carrying the
practical men, too, and all their work may be thrown away, and worse than
thrown away, if they do not take knowledge of them and get out of the wrong
ones and into the right ones as soon as they may.
Sir Edward Parry and his party were going straight towards
the pole in one of their arctic expeditions, travelling at the rate of ten
miles a day. But the ice over which they travelled was drifting straight
towards the equator, at the rate of twelve miles a day, and yet no man among
them would have known that he was travelling two miles a day backward unless he
had lifted his eyes from the track in which he was plodding.
It is not only going backward that the plain practical
workman is liable to, if he will not look up and look around; he may go forward
to ends he little dreams of.
