men once were burned at
the stake for entertaining are now the commonplace axioms of every school
boy's thought; our economics change until schools of thought shaped to
old industrial conditions are as outmoded as a one-horse shay beside an
automobile; our philosophy changes like our science when Kant, for
example, starts a revolution in man's thinking, worthy, as he claimed, to
be called Copernican; our cultural habits change until marooned
communities in the Kentucky mountains, "our contemporary ancestors,"
having let the stream of human life flow around and past them, seem as
strange to us as a belated what-not in a modern parlour. The perception
of this fact of progressive change is one of the regnant influences in
our modern life and, strangely enough, so far from disliking it, we glory
in it; in our expectancy we count on change; with our control of life we
seek to direct it.

Indeed no more remarkable difference distinguishes the modern world from
all that went before than its attitude toward change itself. The
medieval world idealized changelessness. Its very astronomy was the
apotheosis of the unalterable. The earth, a globe full of mutation and
decay; around it eight transparent spheres carrying the heavenly bodies,
each outer sphere moving more slowly than its inner neighbour, while the
ninth, moving most slowly of all, moved all the rest; last of all, the
empyrean, blessed with changeless, motionless perfection, the abode of
God--such was the Ptolemaic astronomy as Dante knew it. This
idealization of changelessness was the common property of all that by
gone world. The Holy Roman Empire was the endeavour to perpetuate a
changeless idea of political theory and organization; the Holy Catholic
Church was the endeavour to perpetuate a changeless formulation of
religious dogma and hierarchy; the Summa of St. Thomas Aquinas was the
endeavour to settle forever changeless paths for the human mind to walk
in. To that ancient world as a whole the perfect was the finished, and
therefore it was immutable.

How different our modern attitude toward change has come to be! We
believe in change, rely on it, hope for it, rejoice in it, are determined
to achieve it and control it. Nowhere is this more evident than in our
thought of the meaning of knowledge. In the medieval age knowledge was
spun as a spider spins his web. Thinking simply made evident what
already was involved in an accepted proposition. A premise