* Dehumanization: This occurs when people are treated as less than human, which makes it easier to commit acts of violence against them. This is often done by denying them their individuality, or by creating stereotypes that make them seem like a threat.
* Need for Power and Control: Some people are driven by a need to control others, and they may use violence as a way to achieve this. They may also enjoy the feeling of power that violence gives them.
* Sadism: This is a psychological disorder that is characterized by a desire to inflict pain on others. People with this disorder may derive pleasure from seeing others suffer.
* Psychopathy: This is a personality disorder that is characterized by a lack of empathy and remorse. People with this disorder may not be able to understand the suffering that their actions cause others.
* Groupthink: This is a psychological phenomenon that occurs when people within a group are pressured to conform to the group's beliefs or decisions. This can lead to people making decisions that they would not normally make, including acts of violence.
* Revenge: This is a desire to retaliate against someone who has caused you harm. Revenge can be a powerful motivator, and it can lead people to commit acts of violence that they would not otherwise consider.
These are just some of the possible causes of human cruelty. It is important to remember that these factors can interact with each other, and that they can also be influenced by other factors, such as culture, history, and social environment.