tending over four hundred or four
thousand centuries. Take biology or astronomy. How can we be sure that
some day progress may not come to a dead pause, not because knowledge
is exhausted, but because our resources for investigation are
exhausted--because, for instance, scientific instruments have reached
the limit of perfection beyond which it is demonstrably impossible to
improve them, or because (in the case of astronomy) we come into the
presence of forces of which, unlike gravitation, we have no terrestrial
experience? It is an assumption, which cannot be verified, that we shall
not soon reach a point in our knowledge of nature beyond which the human
intellect is unqualified to pass.

But it is just this assumption which is the light and inspiration of
man's scientific research. For if the assumption is not true, it means
that he can never come within sight of the goal which is, in the case
of physical science, if not a complete knowledge of the cosmos and
the processes of nature, at least an immeasurably larger and deeper
knowledge than we at present possess.

Thus continuous progress in man's knowledge of his environment, which is
one of the chief conditions of general Progress, is a hypothesis which
may or may not be true. And if it is true, there remains the further
hypothesis of man's moral and social "perfectibility," which rests on
much less impressive evidence. There is nothing to show that he may not
reach, in his psychical and social development, a stage at which the
conditions of his life will be still far from satisfactory, and beyond
which he will find it impossible to progress. This is a question of fact
which no willing on man's part can alter. It is a question bearing on
the mystery of life.

Enough has been said to show that the Progress of humanity belongs to
the same order of ideas as Providence or personal immortality. It is
true or it is false, and like them it cannot be proved either true or
false. Belief in it is an act of faith.

The idea of human Progress then is a theory which involves a
synthesis of the past and a prophecy of the future. It is based on
an interpretation of history which regards men as slowly
advancing--pedetemtim progredientes--in a definite and desirable
direction, and infers that this progress will continue indefinitely. And
it implies that, as

The issue of the earth's great business,

a condition of general happiness will ultimately be enjoyed, which wil