There are few uglier traits of human nature than this tendency — which I now witnessed in men no worse than their neighbours — to grow cruel, merely because they possessed the power of inflicting harm.

Cruelty is one of the chief ingredients of love, and divided about equally between the sexes: cruelty of lust, ingratitude, callousness, maltreatment, domination. The same is true of the passive qualities, patience under suffering, even pleasure in ill usage.

It is a commonplace that men are excessively ruthless and cruel not as a rule out of avowed malice but from outraged righteousness. How much more is this true of legally constituted states, invested with all the seeming moral authority of parliaments and congresses and courts of justice! The destructive capacity of the individual, however vicious, is small; of the state, however well-intentioned, almost limitless.

Then as to cruelty. This is of two kinds, intentional and unintentional. Intentional cruelty is purposely to give pain to another living being; and that is the greatest of all sins — the work of a devil rather than a man. You would say that no man could do such a thing; but men have done it often, and are daily doing it now. The inquisitors did it; many religious people did it in the name of their religion. Vivisectors do it; many schoolmasters do it habitually. All these people try to excuse their brutality by saying that it is the custom; but a crime does not cease to be a crime because many commit it. Karma takes no account of custom; and the karma of cruelty is the most terrible of all.

Cruelty is as old as life itself.

Man has historically devoted much more subtle and ingenious thought to inflicting cruelty than to giving others pleasure — which, given his gregarious nature, would seem a much more survival-oriented behavior. Poll any hundred people at random and you'll find at least twenty or thirty who know all there is to know about psychological torture and psychic castration — and maybe two who know how to give a terrific back-rub.

I shall have to express a very deep conviction: that until we have courage to recognize cruelty for what it is—whether its victim is human or animal—we cannot expect things to be much better in the world. There can be no double standard. We cannot have peace among men whose hearts find delight in killing any living creature. By every act that glorifies or even tolerates such moronic delight in killing, we set back the progress of humanity.

My own belief is that in most ages and in most places obscure psychological forces led men to adopt systems involving quite unnecessary cruelty, and that this is still the case among the most civilized races at the present day.

It is from the Bible that man has learned cruelty, rapine, and murder; for the belief of a cruel God makes a cruel man.

[C]ruelty is cruelty under whatever colouring it may appear; and whether exercised on a man or on a fly, cruelty is still cruelty. It matters not whether the victim be furnished with two legs or with four, with wings, with fins, or with arms; where there is sensation, there is subject for cruelty, and in proportion to the degree of sensation will its action operate.

Cleverness is usually cruel, malicious and selfish; it seeks a weakness in its neighbor and exploits it for its own gain; it leads to success. [...:] Reason is frequently cruel to man, but it is true to its intentions; it seeks to profit everyone ...

What has here happened is that the instinct of cruelty, which has turned inwards, has become self-torture, and all man’s animal instincts have been reinterpreted as guilt towards God. Every Nay man utters to his nature, to his real being, he flings out as a Yea, an affirmation of reality applied to God’s sanctity

The more cruel the wrong that men commit against an individual or a people, the deeper their hatred and contempt for their victim. Conceit and false pride on the part of a nation prevent the rise of remorse for its crime.

Every single act of cruelty contributes something towards generating in the mind an habit of cruelty.