We will now discuss in a little more detail the struggle for existence.

In the survival of favoured individuals and races, during the constantly-recurring struggle for existence, we see a powerful and ever-acting form of selection.

The explanation of types of structure in classes - as resulting from the will of the Deity, to create animals on certain plans - is no explanation. It has not the character of a physical law and is therefore utterly useless. It foretells nothing because we know nothing of the will of the Deity, how it acts and whether constant or inconstant like that of man.

At some future period, not very distant as measured by centuries, the civilized races of man will almost certainly exterminate, and replace the savage races throughout the world.

Ignorance more frequently begets confidence than does knowledge: it is those who know little, and not those who know much, who so positively assert that this or that problem will never be solved by science.

The life of wild animals is a struggle for existence. The full exertion of all their faculties and all their energies is required to preserve their own existence and provide for that of their infant offspring.