The facts have to be determined by empirical evidence, and our thinking has then to conform to the facts, not the facts to our thinking - J. L. Mackie

If we admire and enjoy the flourishing of human life, we shall naturally delight also in the flourishing of animal life.

It is in imaginative literature — including those parts of it which pass for history and biography — that what may be good in human life is concretely represented.

Liberties conflict with one another, and almost any policy whatever can be represented as a defence — direct or indirect — of some sort of liberty. What we need, therefore, is not a general defence of liberty, but adjudication between particular rival claims to freedom.