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1 blocks not present in 1859 1860 1869 1872; present in 1861 1866
I need hardly say that Science in her present state does not countenance the belief that living creatures are now ever produced from inorganic matter.

however, under her present aspect does not countenance the 1869
has not as yet proved the truth of this 1872

reveal, that living creatures are now being generated. 1869
reveal. 1872

or the survival of the fittest, does not necessarily include progressive 1869 1872
includes no necessary and universal law of advancement or 1861 1866

But it may be objected that if all organic beings thus tend to rise in the scale, how is it that throughout the world a multitude of the lowest forms still exist; and how is it that in each great class some forms are far more highly developed than others? Why have not the more highly developed forms everywhere supplanted and exterminated the lower? Lamarck, who believed in an innate and inevitable tendency towards perfection in all organic beings, seems to have felt this difficulty so strongly, that he was led to suppose that new and simple forms
were
are
continually being produced by spontaneous generation.
Science
Science,
however, under her present aspect does not countenance the belief, whatever the future may reveal, that living creatures are now being generated. On
my
our
theory the
present
continued
existence of lowly
organised
organisms
productions
....
offers no difficulty; for natural
selection
selection,
or the survival of the fittest, does not necessarily include progressive development— it only takes advantage of such variations as arise and are beneficial to each creature under its complex relations of life. And it may be asked what advantage, as far as we can see, would it be to an infusorian animalcule— to an intestinal worm— or even to an earth-worm, to be highly
organised.
organised?
If it were no advantage, these forms would be
left,
left
by natural
selection,
selection
unimproved or but little
improved;
improved,
improved:
and might remain for indefinite ages in their present
lowly
little advanced
condition. And geology tells us that some of the lowest forms, as the infusoria and rhizopods, have remained for an enormous period in nearly their present state. But to suppose that most of the many now existing low forms have not in the least advanced since the first dawn of life would be
extremely rash;
rash;
for every naturalist who has dissected some of the beings now ranked as very low in the scale, must have been struck with their really wondrous and beautiful organisation.