269 
Dissipation of Energy, discovered by Sir Wm. Thompson, and 
quoting his three lines of argument, urges “ ten million years 
at the utmost we can give to geologists for their speculations 
as to the history even of the lowest order of fossils, and for 
all the changes that have taken place on the earth's surface 
since vegetable life, of the lowest known form, was capable of 
existing there." And, further, he adds, “ This discovery 
enables us distinctly to say that the present order of things 
has not been evolved through infinite past time by the agency 
of laws now at work, but must have had a distinct beginning 
— a state beyond which we are utterly unable to penetrate ; a 
state which must have been produced by other than the now 
visibly acting causes." 
There are three additional points which I would raise against 
these views before I draw my paper to a close. 
And, first , when we compare man with the savage pro- 
genitors from whom he is developed, we find that his 
development has taken that form which would be most dis- 
advantageous in the struggle for life, according to the theory 
of natural selection. By no one has this point been put more 
admirably than by the Duke of Argyll. “ The direction," says 
he, “ in which the human frame diverges from the structure 
of the brute is in the direction of greater physical helplessness 
and weakness ; but this is not the direction in which the blind 
agencies of natural selection could ever work. The unclothed 
and unprotected condition of the human body, its compara- 
tive slowness of foot, the absence of teeth adapted for pre- 
hension or for defence, the same want of power for similar 
purposes in the hands and fingers, the bluntness of the sense 
of smell, — all these are features which stand in strict and 
harmonious relation to the mental powers of man. But, apart 
from these, they would place him at an immense disadvantage 
in the struggle for existence. These powers when possessed 
could not be modified in the direction of greater weakness 
without inevitable destruction, until first, by the gift of 
reason and of mental capacities of contrivance, there had 
been established an adequate preparation for the change. 
The loss of speech or of climbing powers which is involved 
in the fore-arms becoming useless for locomotion could not be 
incurred with safety until the brain was ready to direct a hand. 
The foot could not be allowed to part with its prehensile power 
until the powers of reason and reflection had been provided 
to justify as it now explains the erect position and the upward 
gaze. If man's frame was once more bestial, it may have 
been better adapted for a more bestial existence ; but it is 
impossible to conceive how it could ever have emerged from 
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