On Tuesday, a man killed a 2-year-old girl after a quarrel with the girl's mother. What makes people so cruel, asks an editorial in Beijing News (excerpts below).

This may be an extreme case but too often we hear about arguments escalating into acts of violence. Many are triggered by trivial concerns.

Some experts in social behavior suggest our society is getting crueler.

The perpetrators must be punished and punished severely.

But a deeper sense of social justice must be promoted.

We must cherish the core values of a decent society.