Why does the idea of progress loom so large in the modern world?
Surely because progress of a particular kind is actually taking place around us
and is becoming more and more manifest.
Although mankind has undergone no general improvement in intelligence or morality,
it has made extraordinary progress in the accumulation of knowledge.
Knowledge began to increase as soon as the thoughts of one individual
could be communicated to another by means of speech.
With the invention of writing， a great advance was made,
for knowledge could then be not only communicated but also stored.
Libraries made education possible, and education in its turn added to libraries:
the growth of knowledge followed a kind of compound interest law,
which was greatly enhanced by the invention of printing.
All this was comparatively slow until, with the coming of science,
the tempo was suddenly raised.
Then knowledge began to be accumulated according to a systematic plan.
The trickle became a stream;
the stream has now become a torrent.
Moreover, as soon as new knowledge is acquired, it is now turned to practical account.
What is called modern civilization is not the result of a balanced development of all mans nature,
but of accumulated knowledge applied to practical life.
The problem now facing humanity is:
What is going to be done with all this knowledge?
As is so often pointed out, knowledge is a two-edged weapon
which can be used equally for good or evil.
It is now being used indifferently for both.
Could any spectacle, for instance, be more grimly weird
than that of gunners using science to shatter mens bodies while, close at hand,
surgeons use it to restore them?
We have to ask ourselves very seriously what will happen if this twofold use of knowledge,
with its ever-increasing power, continues.