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CAUSATION AND EVOLUTION.
Yet whence
entiation?
ences of the two-fold nature-Inner and Outer. (a) The seed is the inner nature of the tree where as the outer is the differ. nature comprises the soil, the water, the heat, the light, and the air. The seed has the potency to develop into a tree and it is only the outer nature that stands as a help to the seed in the exertion of its latent powers for its proper development into a tree; but this outer nature is almost the same to all the different trees. The real difference, therefore, lies in the inner natures' of the different trees i. e. in the seeds. And the same old question comes round yet, Whence is this difference? If it is said in reply that the difference is due to the difference in the relative disposition of the particles constituting the two seeds, then the difference is only explained by another difference which tantamounts to explaining 'X' by 'Y' both of which are unknown quantities and therefore the second difference again has yet to be inquired into. Science stops short here. She does not know. The mystery, though pushed back, remains un
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