Such modification as this is very different from the "survival of the fittest" of the Darwinian evolution theory. We may fairly suppose that both kinds of modification take place; but the latter is a sort of easy success won by an external accident of birth--a success of the kind that would readily be lost again; while the former is the uphill fight of a nature that has grown inwardly and wins expression for itself in spite of external obstacles--an expression which therefore is likely to be permanent. If the progenitors of man took to going upright on two legs instead of on all fours, merely because a few of them by _chance_ were born with a talent for that position, which enabled them to escape the fanged and pursuing beasts, then when this danger was removed they might have plumped down again into the old attitude; but if the change was part and parcel of a true evolution, the fulfilment of a positive desire for the upright position, a true _unfolding_ of a higher form latent within--an organic growth of the creature itself, then, though the moment of the evolution of this particular faculty might be determined by the fanged beasts, the fact of such evolution could not be determined by them. Besides, are we to suppose that Man, the lord and ruler of the animals, came merely by way of _escape_ from the animals? Do lords and rulers generally come so? Was it fear that made him a man? Were it not likelier that in that case he would have turned into a worm? He would have escaped better perhaps that way. Is it not rather probable that it was some nobler power that worked transforming--some dim desire and prevision of a more perfect form, the desire itself being the first consciousness of the urge of growth in that direction--that prompted him to push in the one direction rather than the other when he had to hold his own against the tigers? In fact is it not thus to-day, when a man has to meet danger, that the ideal which he has within him determines _how_ he shall meet that danger, and others like it, and so ultimately determines the whole attitude and carriage of his body?