a just appreciation of
the doctrine of the human destiny of the universe--the doctrine that all
things were made for man. Seen from the sun, the earth dwindles away to
a mere speck, a mere dust-mote glistening in his beams. If the reader
wishes a more precise valuation, let him hold a page of this book a
couple of feet from his eye; then let him consider one of its dots or
full stops; that dot is several hundred times larger in surface than is
the earth as seen from the sun!
Of what consequence, then, can such an almost imperceptible particle be?
One might think that it could be removed or even annihilated, and yet
never be missed. Of what consequence is one of those human monads, of
whom more than a thousand millions swarm on the surface of this all
but invisible speck, and of a million of whom scarcely one will leave
a trace that he has ever existed? Of what consequence is man, his
pleasures or his pains?
Among the arguments brought forward against the Copernican system at the
time of its promulgation, was one by the great Danish astronomer, Tycho
Brahe, originally urged by Aristarchus against the Pythagorean system,
to the effect that, if, as was alleged, the earth moves round the sun,
there ought to be a change of the direction in which the fixed stars
appear. At one time we are nearer to a particular region of the heavens
by a distance equal to the whole diameter of the earth's orbit than we
were six months previously, and hence there ought to be a change in
the relative position of the stars; they should seem to separate as we
approach them, and to close together as we recede from them; or, to use
the astronomical expression, these stars should have a yearly parallax.
The parallax of a star is the angle contained between two lines drawn
from it--one to the sun, the other to the earth.
At that time, the earth's distance from the sun was greatly
under-estimated. Had it been known, as it is now, that that distance
exceeds ninety million miles, or that the diameter of the orbit is more
than one hundred and eighty million, that argument would doubtless have
had very great weight.
In reply to Tycho, it was said that, since the parallax of a body
diminishes as its distance increases, a star may be so far off that its
parallax may be imperceptible. This answer proved to be correct. The
detection of the parallax of the stars depended on the improvement of
instruments for the measurement of angles.
The paralla
|