dragons. Distances have vanished before the patience of the
humble workers of the world, which is reduced to pettiness by
the genius of man. The longest journeys have become well-trodden
promenades; the most gigantic tasks are accomplished under the
potential and tireless hand of this unseen force; a telegraphic
despatch flies, in the twinkling of an eye, from one continent
to the other; without leaving our armchairs, we converse with
the inhabitants of London and Saint Petersburg; yet these
miracles pass unnoticed. We do not dream to what struggles, to
what mortifications, to what persecutions, these wonders are
due; and we do not reflect that the impossible of yesterday has
become the actual of to-day.

There are men who call to us: "Halt, ye small scientists! We do
not understand you! Consequently, you cannot yourselves
comprehend what you are talking about!" We may reply: However
narrow your judgment, your myopia does not afflict all mankind.
It must be declared to you, gentlemen, that in spite of
yourselves, despite your ravings, the chariot of human knowledge
advances further than ever before, and will continue its
triumphal march towards the conquest of new powers.

Like the spasms of Galvani's frog, certain crude facts, about
which you are skeptical, reveal the existence of natural forces
as yet unknown. There is no effect without a cause. The human
being is the least known of all beings within our ken. We have
learned how to measure the sun, to traverse celestial distances,
to analyze starlight; yet we are ignorant as to what we
ourselves are. Man is a double being, _homo duplex_; and this
double nature remains a mystery to himself. We think; but what
is thought? Nobody can say. We walk; but what is this organic
action? Nobody knows. My will is an immaterial force; all the
faculties of my soul are immaterial; nevertheless, if I will to
raise my arm, this volition overcomes matter. How does this
power act? What mediation serves for the conveyance of the
mental command, in order to produce a physical effect? As yet no
one can answer.

Tell me how the optic nerve transmits to our mentality a vision
of external objects! Tell me how thought conceives and where it
resides, and of what nature is cerebral activity! Tell me...!
But no! I could question you for ten