The art required for developing the position in imagination was not of a complicated kind, and yet it is one of the rarest of gifts.

Something more was wanted than simply conceiving what a man in such a situation would probably feel and probably do.

Above all, it was necessary that his perplexities should be unexpected, and his expedients for meeting them unexpected; yet both perplexities and expedients so real and life-like that, when we were told them, we should wonder we had not thought of them before.

One gift was indispensable for this, however many might be accessory, the genius of circumstantial invention--not a very exalted order of genius, perhaps, but quite as rare as any other intellectual prodigy.[5] [Footnote 5: Mr.Leslie Stephen seems to me to underrate the rarity of this peculiar gift in his brilliant essay on Defoe's Novels in _Hours in a Library_.] Defoe was fifty-eight years old when he wrote _Robinson Crusoe_.

If the invention of plausible circumstances is the great secret in the art of that tale, it would have been a marvellous thing if this had been the first instance of its exercise, and it had broken out suddenly in a man of so advanced an age.