THE PRESIDENT’S ADDRESS. 367 
will be necessary briefly to do in order to show the part which has 
been played by physical science. 
During the middle ages the church was in the van of human pro- 
gress. She bound together distant lands by the tie of a common 
belief, a common religious language, a common priesthood. and com- 
mon prayers. Under her influence all |-atin Christians came more 
or less to feel that they were brethren. Before all the nations of the 
rude west was placed a lofty ideal of life ; and into all were intro- 
duced under her auspices some seeds of useful knowledge, of art. of 
learning, and of refinement. The monks improved agriculture in the 
north and west ; every pilgrim that went to Rome brought back new 
ideas ; and the clergy were the conservers and disseminators of the 
little knowledge of the time. But perhaps the most important work 
that the church did in those ages was that which she performed in 
aid of the abolition of serfdom. For lending her powerful assistance 
to the cause of personal liberty she deserves the everlasting gratitude 
of mankind. 
With the abolition of villenage the church ceased to lead. Per- 
sonal freedom led to increased industry, towns sprang up all over 
Kurope, there was a great development of commerce, and wealth 
increased. Increase of wealth led to a greater diffusion and increase 
of knowledge ; this in its turn led to inventions and discoveries ; 
gunpowder revolutionized war ; the printing press multiplied books ; 
the Renascence, or new birth of learning, art, and literature, follows ; 
then comes Luther, and personal freedom has led to a movement 
for spiritual emancipation. 
The revolt of Luther was contemporary with a great outburst of 
imprisoned forces and a great onward movement of humanity. 
Before the middle of the seventeenth century four great national 
literatures had come into being, the English, the French, the Spanish, 
and the Italian. The northern part of Europe became religiously 
independent, and this religious independence was conjoined in two 
eases, England and Holland, with political freedom. The air was 
full of bold and original speculations, and nature began for the first 
time in the history of man to find herself interrogated with success. 
The first great event in the history of science is the establishment 
of the heliocentric theory by Copernicus. Copernicus was a 
contemporary of Luther, dying just three years before him, and, 
though he lived and died in the old faith, was, in his own way, 
