England--the "land of
common-sense," as a German scientist has called it--"a cool, clear, and
unprejudiced spirit," who in the golden age of systems declined "to be
like the man who builds the chambers of the upper story of his house
before he had laid securely the foundation walls."(1) This man was
Thomas Sydenham (1624-1689), who, while the great Harvey was serving the
king as surgeon, was fighting as a captain in the parliamentary army.
Sydenham took for his guide the teachings of Hippocrates, modified to
suit the advances that had been made in scientific knowledge since the
days of the great Greek, and established, as a standard, observation and
experience. He cared little for theory unless confirmed by practice, but
took the Hippocratic view that nature cured diseases, assisted by the
physician. He gave due credit, however, to the importance of the part
played by the assistant. As he saw it, medicine could be advanced in
three ways: (1) "By accurate descriptions or natural histories of
diseases; (2) by establishing a fixed principle or method of treatment,
founded upon experience; (3) by searching for specific remedies, which
he believes must exist in considerable numbers, though he admits that
the only one yet discovered is Peruvian bark."(2) As it happened,
another equally specific remedy, mercury, when used in certain diseases,
was already known to him, but he evidently did not recognize it as such.

The influence on future medicine of Sydenham's teachings was most
pronounced, due mostly to his teaching of careful observation. To most
physicians, however, he is now remembered chiefly for his introduction
of the use of laudanum, still considered one of the most valuable
remedies of modern pharmacopoeias. The German gives the honor of
introducing this preparation to Paracelsus, but the English-speaking
world will always believe that the credit should be given to Sydenham.

IX. PHILOSOPHER-SCIENTISTS AND NEW INSTITUTIONS OF LEARNING

We saw that in the old Greek days there was no sharp line of demarcation
between the field of the philosopher and that of the scientist. In the
Hellenistic epoch, however, knowledge became more specialized, and our
recent chapters have shown us scientific investigators whose efforts
were far enough removed from the intangibilities of the philosopher. It
must not be overlooked, however, that even in the present epoch there
were men whose intellectual efforts were primarily direc