Words of intimidation that start as figures of speech can cast a pall over an environment that already has a built-in susceptibility to extreme language.

A few days ago, Wang Mudi, a television host in Guangdong province, accompanied his girlfriend to the hospital. The nurse did an extremely sloppy job putting her on a drip. It took her four attempts to properly inject the needle. All the while she was carrying on a casual conversation with a colleague.

Wang was so enraged he wrote on his Sina Weibo account, a Chinese micro blog, that "I felt I wanted to hack someone". The next day, a healthcare industry association demanded he apologize or his employer should sack him.

Most online denizens seemed to agree that what Wang did exacerbated China's troubled doctor-patient relations. A recent spate of incidents where patients or their family members resorted to violence and physically harmed members of medical services has raised alarm about the vulnerability of the profession. Previously, however, the media portrayed medical professionals as greedy merchants who coerced bribes from patients.

Some say Wang got away too lightly, especially compared with Wu Hongfei. Wu, a singer and writer, made news six months ago when she was arrested for posting threatening words on her blog. She said she "wanted to blow up the neighborhood committee" and a few other government agencies. She was detained for 10 days and fined 500 yuan ($82), but not prosecuted, possibly because of public pressure. She was said to have violated two clauses of the law, including "claims to use arson, explosion or harmful material to disturb public order" and "fabricating and purposefully distributing false or horror-inducing information".

Do I believe that Wang is a potential killer and Wu a potential arsonist? Not for a minute. It's a way to let off some steam. I can totally understand their frustration. We've all been in situations when clenching our teeth was not enough.

But what they did was wrong. Weibo is a public platform. Shouting "I want to kill him!" in the privacy of your home is not the same as saying it to hundreds of thousands of people. (Wang has 377,500 followers on his weibo account and Wu 133,100.) What if someone, like the police, takes you verbatim? You may laugh at the police for an unhealthy deficiency in humor, but you would definitely point a finger of blame at them if - and it's a big if - the person who posted it actually went out and did something bad but they had assumed it was just an articulation of anger.