not a few
open friends. It found many minds eager to receive {508} and able to
appreciate it. Among these were Leonardo da Vinci, who proclaimed
the fundamental principle that experiment and observation are the
only reliable foundations of reasoning in science, that experiment
is the only trustworthy interpreter of Nature, and is essential to
the ascertainment of laws. He showed that the action of two
perpendicular forces upon a point is the same as that denoted by the
diagonal of a rectangle, of which they represent the sides, etc."

We must suppose that the scientific readers of this book, for they
were mainly scientists, and it had a place in the International
Scientific Series, agreed with this marvellous exhibition of
ignorance. Here is a man summarizing modern European science and
leaving out all mention of Albertus Magnus, Roger Bacon, the great
medical school of Salerno in the twelfth century, and the great
medical schools of Italy farther north during the thirteenth,
fourteenth, and fifteenth centuries. This lack of knowledge of the
history of medicine deserves, above all, to be emphasized because
Draper as a professor in a medical school would naturally be supposed
to know something about his own branch of science.

He attributes all the initiative of modern science to the impulse
derived from the Arabs. This used to be a favorite way of looking at
the history of culture for those who wanted to minimize just as far as
possible all Christian influence. The facts of history are in constant
contradiction with this. Modern European science began at the
University of Salerno. It has often been stated that Arabian influence
must have largely impelled Salerno's work, situated as it was in the
southern part of Italy, but the use of any such expression means that
the writer must forget that this southern part of Italy had been a
Greek colony, was indeed called Magna Graecia and that Greek influence
persisted there, and when the revival came after the Barbarians who
had invaded Italy had gradually been brought by religious influence
into a state where culture and science and civilization were to mean
something for them, the influence of the old Greek authors was first
felt here. Gurlt, in his History of Surgery, emphasizes the fact, for
instance, that the first important modern (or medieval) writers on
surgery, the Four Masters of Salerno, were not influenced by the
Arabs. Their books contain no Arabi