The first essential character [of civilization], I should say, is forethought. This, indeed, is what mainly distinguishes men from brutes and adults from children.

If you had the power to destroy the world, would you do so?

Physics, owing to the simplicity of its subject matter, has reached a higher state of development than any other science.

What we cannot think we cannot think, therefore we also cannot say what we cannot think.

History is valuable, to begin with, because it is true; and this, though not the whole of its value, is the foundation and condition of all the rest. That all knowledge, as such, is in some degree good, would appear to be at least probable; and the knowledge of every historical fact possesses this element of goodness, even if it posses no other.

We shall say that we have acquaintance with anything of which we are directly aware, without the intermediary of any process of inference of any knowledge of truths.

From India to Spain, the brilliant civilization of Islam flourished. What was lost to christendom at this time was not lost to civilization, but quite the contrary.