others; it follows, that the amount of organic change in the fossils of
consecutive formations probably serves as a fair measure of the lapse
of actual time. A number of species, however, keeping in a body might
remain for a long period unchanged, whilst within this same period,
several of these species, by migrating into new countries and coming
into competition with foreign associates, might become modified; so
that we must not overrate the accuracy of organic change as a measure
of time. During early periods of the earth s history, when the forms of
life were probably fewer and simpler, the rate of change was probably
slower; and at the first dawn of life, when very few forms of the
simplest structure existed, the rate of change may have been slow in an
extreme degree. The whole history of the world, as at present known,
although of a length quite incomprehensible by us, will hereafter be
recognised as a mere fragment of time, compared with the ages which
have elapsed since the first creature, the progenitor of innumerable
extinct and living descendants, was created.
In the distant future I see open fields for far more important
researches. Psychology will be based on a new foundation, that of the
necessary acquirement of each mental power and capacity by gradation.
Light will be thrown on the origin of man and his history.
Authors of the highest eminence seem to be fully satisfied with the
view that each species has been independently created. To my mind it
accords better with what we know of the laws impressed on matter by the
Creator, that the production and extinction of the past and present
inhabitants of the world should have been due to secondary causes, like
those determining the birth and death of the individual. When I view
all beings not as special creations, but as the lineal descendants of
some few beings which lived long before the
first bed of the Silurian system was deposited, they seem to me to
become ennobled. Judging from the past, we may safely infer that not
one living species will transmit its unaltered likeness to a distant
futurity. And of the species now living very few will transmit progeny
of any kind to a far distant futurity; for the manner in which all
organic beings are grouped, shows that the greater number of species of
each genus, and all the species of many genera, have left no
descendants, but have become utterly extinct. We can so far take a
prophetic glance into futurity as to foretel that it will be the common
and widely-spread species, belonging to the larger and dominant groups,
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