An introduction to mathematics, by A. N. Whitehead.

CHAPTER XV
THE DIFFERENTIAL CALCULUS
THE invention of the differential calculus
marks a crisis in the history of mathematics.
The progress of science is divided between
periods characterized by a slow accumulation
of ideas and periods, when, owing to the new
material for thought thus patiently collected,
some genius by the invention of a new method
or a new point of view, suddenly transforms
the whole subject on to a higher level. These
contrasted periods in the progress of the
history of thought are compared by Shelley
to the formation of an avalanche.
The sun-awakened avalanche! whose mass,
Thrice sifted by the storm, had gathered there
Flake after flake, - in heaven-defying minds
As thought by thought is piled, till some great truth
Is loosened, and the nations echo round,
The comparison will bear some pressing.
The final burst of sunshine which awakens
the avalanche is not necessarily beyond comparison in magnitude with the other powers
of nature which have presided over its slow
217