So living Nature, not dull Art, Shall plan my ways and rule my heart. - John Henry Newman

Now what is it that moves our very hearts and sickens us so much at cruelty shown to poor brutes? I suppose this first, that they have done no harm; next that they have no power whatever of resistance; it is the cowardice and tyranny of which they are the victims which makes their sufferings so especially touching. For instance, if they were dangerous animals, take the case of wild beasts at large, able not only to defend themselves, but even to attack us; much as we might dislike to hear of their wounds and agony, yet our feelings would be of a very different kind; but there is something so very dreadful, so satanic, in tormenting those who never have harmed us, who cannot defend themselves, who are utterly in our power, who have weapons neither of offence nor defence, that none but very hardened persons can endure the thought of it.

It is almost a definition of a gentleman to say he is one who never inflicts pain.

Where good and ill together blent,
Wage an undying strife.