The moral duty to be expected in different ages is not a unity of standard, or of acts, but a unity of tendency ... At one time the benevolent affections embrace merely the family, soon the circle expanding includes first a class, then a nation, then a coalition of nations, then all humanity and finally, its influence is felt in the dealings of man with the animal world.

The contraction of theological influence has been at once the best measure, and the essential condition of intellectual advance.

It had been boldly predicted by some of the early Christians that the conversion of the world would lead to the establishment of perpetual peace. In looking back, with our present experience, we are driven to the melancholy conclusion that, instead of diminishing the number of wars, ecclesiastical influence has actually and very seriously increased it.

When it began, Christianity was regarded as a system entirely beyond the range and scope of human reason; it was impious to question; it was impious to examine; it was impious to discriminate. On the other hand, it was visibly instinct with the supernatural. Miracles of every order and degree of magnitude were flashing forth incessantly from all its parts.

There are some poisons which, before they kill men, allay pain and diffuse a soothing sensation through the frame. We may recognize the hour of enjoyment they procure, but we must not separate it from the price at which it was purchased.

The period of Catholic ascendancy was on the whole one of the most deplorable in the history of the human mind. . . . The spirit that shrinks from enquiry as sinful and deems a state of doubt a state of guilt, is the most enduring disease that can afflict the mind of man. Not till the education of Europe passed from the monasteries to the universities, not till Mohammedan science, and classical free thought, and industrial independence broke the sceptre of the Church, did the intellectual revival of Europe begin.

Anxiety and Ennui are the Scylla and Charybdis on which the bark of human happiness is most often wrecked.