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then, we kill an animal suddenly, without allowing it to experi- 
ence the sense of pain, how have we keen guilty of cruelty ? It 
has no knowledge of the intention we have had of killing it ; it 
has the most perfect enjoyment of life to the last moment. It 
knows not of our having anything to do with its death. In fact, 
it is killed without having had an idea of mortality. Then what 
is the injury inflicted ? 2. But there is another and vastly more 
important argument. This is the one which is furnished in the 
most convincing form in Mr. Darwin’s 66 Origin of Species.” 
It is in four words, 66 The struggle for life.” I suppose 
my anti-vivisectionist friends are unaware of the fact, 
but nevertheless fact it is, that if all the animals that 
were brought into the world during the last fifty years were 
allowed to live for their natural term of years or months, as the 
case may be, the country would be over-run, there would not be 
standing room in all probability for one of us. Living would be 
utterly out of the question, if such a condition existed, for the 
lower animals alone. 
Let us take a few well-known examples from Mr. Darwin’s 
book in proof of this statement. In the sixth edition (the last 
but one), p. 50, of his “ Origin of Species,” the author gives the 
following example of the geometrical ratio of increase, which 
shows us clearly enough that for one animal of any kind that 
lives, thousands perish before reaching maturity; and that were it 
not bo, the world would become uninhabitable : — 
66 A struggle for existence inevitably follows from the high 
rate at which all organic beings tend to increase. Every being 
which during its natural lifetime produces several eggs or 
seeds must suffer destruction during some period of its life, and 
during some season or occasional year. Otherwise , on the prin- 
ciple of geometrical increase , its numbers would quickly become 
so inordinately great that no country could support the pro- 
duct. Hence , as more individuals are produced than can 
possibly survive , there must in every case be a struggle for 
existence It is the doctrine of Malthus applied with 
manifold force to the whole animal and vegetable kingdoms. 
.... Although some species may be now increasing more or less 
rapidly in numbers, all cannot do so, for the world would not 
hold them.” 
“ There is no exception to the rule that every organic being 
naturally increases at so high a rate that if not destroyed the 
earth would soon be covered with the progeny of a single pair. 
Even slow-breeding man has doubled in twenty-five years ; and 
at this rate in less than a thousand years there would literally 
not be standing-room for his progeny. . . . The elephant is 
reckoned the slowest breeder of all known animals, and I have 
taken some pains to estimate its probable minimum rate of 
