ay that a bird has not flown over a desert because it has left no
footprints in the sand. And as with morals, so it is with religion.
Science will allow us to deny or to affirm both. Reason will not allow
us to deny or affirm only one.

FOOTNOTES:

[33] The argument has been used in this exact form by Professor
Clifford.

[34] _Dreams and Realities_, by Leslie Stephen.

[35] The feebleness and vacillation of Dr. Tyndall's whole views of
things, as soon as they bear on matters that are of any universal
moment, is so typical of the entire positive thought of the day, that I
may with advantage give one or two further illustrations of it. Although
in one place he proclaims loudly that the emergence of consciousness
from matter must ever remain a mystery, he yet shows indication of a
hope that it may yet be solved. He quotes with approval, and with an
implication that he himself leans to the view expressed in them, the
following words of Ueberweg, whom he calls '_one of the subtlest heads
that Germany has produced_.' '_What happens in the brain_, says
Ueberweg, '_would in my opinion not be possible if the process which
here appears in its greatest concentration, did not obtain generally,
only in a vastly diminished degree. Take a pair of mice, and a cask of
flour. By copious nourishment the animals increase and multiply, and in
the same proportion sensations and feelings augment. The quantity of
these preserved by the first pair is not simply diffused among their
descendants, for in that case the last would feel more fully than the
first. The sensations and the feelings must necessarily be referred back
to the flour, where they exist, weak and pale, it is true, and not
concentrated, as in the brain._' '_We may not_,' Dr. Tyndall adds, by
way of a gloss to this, '_be able to taste or smell alcohol in a tub of
fermented cherries, but by distillation we obtain from them concentrated
Kirschwasser. Hence Ueberweg's comparison of the brain to a still, which
concentrates the sensation and feeling pre-existing, but diluted, in the
food._'

Let us now compare this with the following. '_It is no explanation_,'
says Dr. Tyndall, '_to say that objective and subjective are two sides
of one and the same phenomenon. Why should phenomena have two sides?
There are plenty of molecular motions which do not exhibit this
two-sidedness. Does water think or feel when it runs into frost-ferns
upon a window pane? If not, why should the molecul