Now, it will be clear from these illustrations, which might be multiplied indefinitely, that the classic philosophy, the philosophy of idealism properly so called, which underlies all religion, whether Platonic or Christian, has been regarded by most thinking men from ancient times to the present day as a conservative, or at least as a regulative, force in society. But thinking men have differed profoundly in their valuation of such a force. Those who hold this philosophy to be true are naturally undivided in their opinion that its social function is beneficial; but those sceptically and materialistically inclined, to whom the spiritual world of Plato and St. Augustine is merely an insubstantial fabric wrought out of the discontent of mankind with the actualities of life, have been divided in their attitude. By some this dream of the unseen, though a deception, has been accepted as necessary for the ordered welfare of society; the enlightened few might indulge their superiority of doubt, but without the restraining content born of superstition the turbulent desires of the masses would throw the world into anarchy and barbarism and universal misery. That was the prevalent attitude of ancient rationalism; and it is still common enough to-day among those who have a condescending respect for the church as a useful ally of the police court. To others, a rapidly growing number, it seems that the spirit of content engendered by religion, if based on a falsehood, must be detrimental to the progress of mankind. Or perhaps their position might be expressed more accurately by reversing the terms. They would not say that religious content is false and therefore must be detrimental; but, rather, religious content is inimical to progress and therefore must be false. I am not here before you to-day to determine the truth or falsehood of the ideal philosophy which supports religious institutions; that is a question which for the present we may waive. We will not discriminate between those who hold this philosophy to be true and those who regard it as an illusion, but an illusion necessary for the preservation of society. The line for us is drawn between those who, for whatever reason, cling to a religious philosophy of the unseen and those who denounce such a philosophy as a check to the progress and prosperity of the race. And you will see at once that the issue between these two classes has been sharpened for us of the present day by the intrusion into sociology of a new theory of existence--new at least in its scope and claims. I mean the great and all-devouring doctrine of evolution.