See R. C. McCrea, The Humane Movement (1910, repr. 1969); L. G. Housden, The Prevention of Cruelty to Children (1955); P. P. Hallie, The Paradox of Cruelty (1969); D. Bakan, Slaughter of the Innocents (1971).
Cruel ways of inflicting suffering may involve violence, but violence is not necessary for an act to be cruel. For example, if another person is drowning and begging for help, and another person is able to help, but merely watches with disinterest or perhaps mischievous amusement, that person is being cruel — rather than violent.
Cruelty usually carries connotations of supremacy over a submissive or weaker force.
According to Richey Edwards, "The centre of humanity is cruelty / There is never redemption / Any fool can regret yesterday".
According to Ian McEwan, the Booker Prize winner in 1998, "novels are not about 'teaching people how to live, but about showing the possibility of what it's like to be someone else. It's the basis of all sympathy, empathy and compassion. Other people are as alive as you are. Cruelty is a failure of imagination'.
Harvard University Professor Judith N. Shklar's thinking is based on two main beliefs: that cruelty is the greatest evil, and her idea of "liberalism of fear".
Victor Nell, of the Institute for Social and Health Sciences at the University of South Africa, wrote a target article in 2005 entitled "Cruelty's Rewards: The Gratifications of Perpetrators and Spectators".