Lol. Every noticed how people like to laugh at other people getting hurt? Ever noticed how people like to bash and hate on others (celebrities mainly) whom they wouldn't even know? I could make a huge 一覧 about everyday things that I'll bet everyone has done that could be considered harsh and irrational. But yeah, humans are cruel.
あなた can't say that in general , it depends on , how were they brought up , cruel depends on how much did the human suffer and no one helped him あなた see the cruel humans ,cause their 愛 for each other has disappeared and they look for their own matters ,they don't think about ,how can they damage others life
Albert Einstein 発言しました that "men have in them a need to hate and destroy" He was right. Most humans start out as cruel in there childhood. They either change as they grow older, または they stay just as malicious.