So far as we yet know, morality rests upon a sense of obligation; and obligation has no meaning except as implying a Divine command, without which it would cease to be. Until 'duty' can be presented to us in a shape which will compel our recognition of it with equal or superior force, the passing away of 'the conviction of sin' can operate only to obscure our aspirations after a high ideal of life and character. The scientific theory may be correct, and it is possible that we may be standing on the verge of the most momentous intellectual revolution which has been experienced in the history of our race. It may be so, and also it may not be so. It may be that the most important factors in the scientific equation are beyond the reach of human intellect. However it be, the meat which gives strength to the man is poison to the child; and as yet we are still children, and are likely to remain children. 'Every relief from outward restraint,' says one who was not given to superstition, 'if it be not attended with increased power of self-command, is simply fatal.' Men of intelligence, therefore, to whom life is not a theory, but a stern fact, conditioned round with endless possibilities of wrong and suffering, though they may never again adopt the letter of Bunyan's creed, will continue to see in conscience an authority for which culture is no substitute; they will conclude that in one form or other responsibility is not a fiction but a truth; and, so long as this conviction lasts, the 'Pilgrim's Progress' will still be dear to all men of all creeds who share in it, even though it pleases the 'elect' modern philosophers to describe its author as a 'Philistine of genius.'