This is the only quality that mentally strong people have

This is the only quality that “mentally strong” people have, according to one psychiatrist: “Write this down.”

A psychiatrist has discovered what “mentally strong” people do and what others should do.

Dr. Daniel Amen from the USA said that mentally strong people practice self-discipline by not doing nice things to those who do not treat them with respect.

The 69-year-old said he raised his children with the mantra to ensure they grow up “mentally strong” and said the habit can “change the world” of those who adopt it.

“Mentally strong people have self-discipline and what I mean by that; They only do nice things for people who treat them with respect,” he said in an online video.

'Write this down.'

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The psychiatrist Dr.  Daniel Amen said spiritually strong people exercise self-discipline by not doing nice things for those they don't treat with respect (stock photo)

The psychiatrist Dr. Daniel Amen said spiritually strong people exercise self-discipline by not doing nice things for those they don't treat with respect (stock photo)

Dr. Amen encouraged fans to “reinforce” the idea in their lives, saying: “The whole world will be different.”

“It is a statement I use with my children to raise mentally strong children,” he added.

Many praised the doctor for imparting the “simple but brilliant” life lesson.

'Makes sense. Be kind to everyone. But only do NICE THINGS *FOR* those who make no secret of respecting you,” one woman explained.

“I literally need this thank you,” said another.

“When I found out, I ended up with almost no friends left and I'm okay with that,” a third commented, and someone replied: “You get good friends with that attitude.” Those who have self-respect and discipline will be attracted to you.”

But not everyone agreed with the hot take, as one viewer pointed out: “It takes more mental strength to do nice things for people who don't respect you.”

“My problem is that I can't tell if people are disrespecting me or if I'm overthinking and being too sensitive,” someone said.